Given that, I guess the best way to evaluate this game is to look at how it stacks up on the core elements of crazy houses. The first and most important elements are, of course, size and puzzles, and so I should start by saying that it's a large game. Standards have slipped in these degenerate modern days, so let me clarify that we are talking a standard walkthrough of two thousand moves. That isn't my turn count — I had closer to six thousand moves by the end of the game — that's the no-wasted-moves walkthrough written by the author herself (albeit with a number of detours to see the hidden corners of the game).
Finding Martin is not particularly large room-wise, but it's crammed full of puzzles. These are of wildly varying size — some are short and require just manipulating a single object, while others are elaborate and require bits from literally a dozen rooms (I am thinking here in particular of a time-travel puzzle that puts the chute in Sorcerer to shame). They're also of varying quality — many of the puzzles range between fun and delightful to solve, but there are also many others that are either too trivial or require extensively reading the author's mind/walkthrough.
The next important question is what kind of use the game makes of the house. A good rule of thumb in checking if the house is being used to its fullest extent is whether the kitchen and bathroom of the house play an important role in the game, and I am pleased to say that in Finding Martin they both do. The house also has a front yard, an extensive backyard, a large dining room (really, irritatingly large, but oh well), and an upstairs (which I am pleased to note is reached in an entertaining way — for some reason crazy houses scorn things as simple as stairs to connect their floors, preferring instead to stick with baroque elevator-like devices). One of the few problems I had with the house is I don't think there are enough connecting passages. It's common in the genre to have areas in the game link up as the game goes on to make it easier to walk around, and while Finding Martin does this, it doesn't do it as much as I would like.
Another important setting consideration in a crazy house is what sort of other areas the PC travels to that aren't directly in the house. Crazy house games tend to be both be defined by and fight against the structure of the house. Finding Martin is a perfect example here, sending the PC to shopping malls, outer space, and someplace near Bora Bora, all as part of exploring the house. The curious thing is that these sort of excursions don't make it feel like the PC is exiting the house — on the contrary, they make it feel like all these places are contained within the house, which just becomes the bigger for it. Another classic house trope is to extend the travelling to going across time, and, though it's no First Things First, Finding Martin makes strong use of this convention too.
The next crazy house measuring point is one that's close to my heart and clearly close to Wennstrom's heart as well. I speak, of course, of the quality of the gadgets in the house. Or, in other words, how awesome would it be to be twelve years old and live in this house? To back up my claim that it would be completely awesome to the infinite power, I need say nothing more than that there is a train track that runs through the house that enables a little model train to move things from room to room, and in fact deliver room service from the kitchen. And this isn't even getting into how you get water in the bathtub, or how Martin opens his closet, or what exactly is in the upstairs bedrooms. I haven't played Hollywood Hijinx, which I understand is also quite strong in this department, but I would still say Finding Martin is a strong contender for Best Crazy House Gadgets Ever.
The last things on my priority list, as is only appropriate for the genre, are the plot and NPCs and backstory and so on. These frankly aren't that important, but Finding Martin does a perfectly serviceable job. The main trick here is for the author to convince us that the plot isn't a thinly put-together excuse to put in a bunch of puzzles, and Wennstrom does that just fine. This game actually has a slight twist on the genre, since the house was not built by Martin — it was actually built by his dad, and Martin's entire family plays a real role in the plot of the game. The game also does some interesting things with cutscenes. Many games try and keep cutscenes short and to the point. Finding Martin has revealed to me that the real thing to do with cutscenes is be bold and take great leaps — the game has no compunction about using a cutscene to take me from flying through the air to locked up in the hold of a pirate ship while a battle rages all around, and it totally works. As long as it's entertaining and fast-paced I am totally willing to be dragged along for the ride. The one problem I had with the plot is I'm afraid the endgame is very weak. It's extremely short, for one thing, and it seems almost purposely designed as a two-step process to defuse any sort of climax. But the upside of it being short is that it's over quickly, and I could get on to the satisfaction of having completed the game.
I think I've pretty thoroughly covered all the details of the game that are crazy-house-specific, and on the whole Finding Martin does quite well on this scale. But there's one major area that I haven't talked about yet, and it's there where I'm afraid the game falls down the most. This area is the, well, gameplay itself. Though it's by no means unplayable, the game is full of minor irritants. These range from things like the conversation system (it's never >ASK NPC ABOUT X, it's always >SAY "X" TO NPC) to pushing buttons (there is frequently cause to do >PUSH 3 but the only syntax allowed is >PUSH "3") to many situations where trying some command results in being told to try some other phrasing instead or do something else first instead of just, you know, doing it for me. There are also some technical weirdnesses with the game — I can't pin it all down, but some of the scoping rules are very strange in this game, with things being referrable-to across rooms but not generally usefully.
There's also the issue of player guidance, or lack thereof. This won't be a problem to die-hard puzzlers of the old school, who will happily pound on every object in the game repeatedly until they discover what they can work on next, but more modern players will probably be turning to the walkthrough for some kind of hint as to what area to work on next. You can definitely do exploring on your own, but the fact that the game can be made unwinnable made me nervous about relying on it too much. I suppose both of these point to a certain lack of beta-testing, but on the other hand I didn't find any actual bugs as such, and the loving attention that was obviously lavished on the game shows it can't have been too neglected.
If you've read this far, it should be pretty obvious if you want to play Finding Martin or not. It's not a minor commitment, but if you haven't played a game this size in a while, and you have a few weeks (and ideally a friend to play it with), I definitely suggest picking it up. There's a whole lot of game here, and all the effort it calls for won't go unrewarded.