Guys this will be fast and sweet. The good and bad in general. And a few specific complaints.
The overall price off the sets is good and the quality is good overall as well.
The scatter bits (crates and such) is great looking.
The terrain works great for bits for conversions.
The terrain works great for small solid structures (1x1, 2x1, even 3x1).
Overall the sets take a lot of work to make look good because of the amount of time it takes just to get everything to fit together properly. (Be prepared to sand and such a lot just for connecting them)
Overall I found the connectors to be hit and miss depending on the piece. Even when unpainted, I cant see the "you can change it every time without much difficulty" actually being what they claim if you try to paint and then assemble as needed.
Bigger structures (even 2x2) really suffer from structural problems with the roof and assembling them can be highly annoying.
Now for a few specifics-
Urban sets- Overall I have had great luck with this series and find that they are very usable for other things as well.
Ruins- Looks great and have gone together the easiest for me. Has a lot of great details.
Fortified- The basic parts are mostly from the urban set but the "fortified" add on pieces are ABSOLUTE HELL ON EARTH, these things are a massive pain to assemble and take a ridiculous amount of time to get just basically built. I found some useful for making scatter terrain but for actually making the fortified buildings it is just not worth the effort.
The scatter terrain is great. The urban stuff is ok with a little work and has decent detail. The ruins are great and I can't wait to try some new painting things on them. Fortified suck.. All the terrain paints up nicely though some also have killer mold lines. Overall, I have found that the idea is great in general but the production is not accurate enough to make it as seemless as they wanted. Is a great way to fill your table with cheap small buildings though. The biggest winner is the scatter terrain, which I will definitly buy more off in the future.
If you have any questions feel free to ask.