Slabs properly constructed on stable grounds will probably last longer and have fewer issues than pier foundations and subfloors in our area. I've owned several and never had any more issues than above grade. As J. Scott mentioned you can bypass problems.
The consideration to be given is that quality or construction method common for the area?
In the south LA. the water table is so high you'll find most homes are on slabs.
I'd caution against a construction method used that's not common, it could be some builder was experimenting to cut costs or maybe putting in an efficient floor heating system, the first build of something usually has a high learning curve where mistakes can be made.
There are advantages and disadvantages to both methods. Slabs can be hard to walk on, colder in the winter if the heat fails, they can sweat in hot humid weather causing tack strip to rot. The good is that you don't have issues with heavy items, floors don't shrink and contract like wood, won't have settlement issues of sloping floors and the don't burn.
If it's common for the area I see no reason to avoid them. Long ago we had to guess where things ran, today you can have lines located before you buy and ensure locations. What I'd rather not see is water supply lines in an attic dropping down! :)