My first attempt at a modular system was with GHQ's foam Geo-Hex system (I realized after writing this that Geo-Hex is a different product the GHQ one is called Terrain Maker)
In 15mm I have made a few set piece terrain items but I have made no effort to make them modular -- except in the case of the pontoon bridge where I made sure the river would fit with the Battlefront rivers that I use. I think that for most 15mm games I want to have complete flexibility of the map to make what ever I need but I still like the look of all those set-pieces. The farm, for example, looks much better with everything in place rather than just randomly placed. And some like Monte Cassino are big enough that they really just define the map on their own. As you can see from the photos, I never got around to finishing off the edges!
In 28mm games I play the maps are different -- smaller (2'x2' to 4'x4' vs the 4'x8' that my 15mm games are) and generally have one main focus such as a single building or group of buildings. (I guess my Hail Caesar games don't really follow this pattern but I don't plan to use the terrain tiles for them). There is less need for complete flexibility in this case and there is greater scope for adding in detailed terrain both of which make terrain tiles more attractive.
My long term plan is to make tiles for each of the buildings I have -- the motel might be a set of tiles but even in that case they will probably only go together one way. In the short term to see if the tile concept really does work for me I will get the 3x3 starter set and work up some road and open ground pieces. The big concern I have with the wavy edges is how the boundary between tiles will be handled -- my basic "edge-crossing" terrain will be a road bounded by a sidewalk. I am going to use sandpaper as the base material for my paved roads so that can be cut to match the edge but the sidewalks are likely to be more tricky. The one thing I learned from doing the SAGA terrain last Christmas time is that the actual terrain you make is always better than the perfect terrain you don't make so I will just charge on an hope for the best
I have ordered the starter set and am planning to work on it over the Labour Day weekend but I have never been particularly good at sticking to those plans!
. I really didn't do much with it as I didn't really have much in the way of skills or money at the time (this would have been late high school - early university) but even the little bit of work we did on it made me think that it was ok for hills (but the hexes weren't much of an advantage over a single piece of Styrofoam) and would be good for a sunken river but to do a whole table size of flat terrain was just extra work
