I've used the D&D dungeon tiles and the Gamemastery basic flip-mat. My preferred one is the flip mat. The issue I had with the dungeon tiles is the time it takes to rebuild the maps (we do not use my house for gaming, so I cannot prebuild the map). It seems to interrupt the game flow more than I like. Making a quick sketch on the flip-mat might not be as pretty, but it keeps the game flowing quickly.
To stop the dungeon tiles from sliding everywhere, I bought a roll of drawer liner (like for a kitchen drawer). Get the one that is kind of spongy, the tiles stick pretty well and don't slide around. But I still prefer the flip mat.