Grimrock doesn't do much for me by the looks of it. Main features to stop my purchase are:
No random map generation so limited replayability.
No map editor so no long life
Not turn based
Also marketed as taking Dungeon Keeper style gameplay - not seeing this at all sorry.
FE Beta3 FTW!
Very different to Dungeon keeper.
It does have a map editor of sorts, IIRC a map can easily be created in notepad!
These sorts of games rarely come with random dungeons (Hack! by TSR being the only one I can think of that did). Also they are rarely turn-based, are you sure you are thinking of the right style of game? It is Tile based however the same as the old school games.
In fact old School is on a bit of a revial, what with Wasteland 2 being made, and with the original team that created it (and fallout 1, fallout 2, Baldur's Gate etc.) In fact this Wasteland project is probably the most excited I have been about an upcoming game ever. The dream team of RPG's coming back together to make an old school game that doesn't give a shit about how 'new gamers or console players' feel about the game. take this quote from an interview for example:-
MF: There seem to be two halves of the gaming universe. Old guys like me who grew up on Fallout. I remember pouring over decisions and redoing combat, just because an NPC died. I loved that dog too much to let him go. The other half, though, are much younger. Their first introduction to the universe was Fallout 3 and New Vegas. How are they going to be able to relate to this game having no real frame of reference for these classic, wonderful RPGs?
BF: The thing about this project being fan-funded is that I’m not worried about this new group of people and how they might get it. This is being made for people like yourself that grew up playing Wasteland, Fallout and Fallout 2. These new people, who have never played these games, I think they’re going to check it out and have a great time. I’m simply not going to worry about how I get these console guys to come over and like it, because there is no reason to. We all know the experience that we grew up with. We all loved it and we’ve all been wanting one, so that’s what I’m going to bring. It’s not a putdown on the console product, it’s just that I’m not going to worry about how to get them.
That was a bit of a tangent, but I get excited about old school RPG's 
