There are probably no more issues than with a monolithic or floating slabs and some would say crawlspaces are easier to see.

I would venture to say that in my opinion Post Tension is probably better, the ability to pull concrete together helps to avoid the pitfalls of cracks developing. Crawlspaces can be tricky because I have seen some that were impossible to crawl, less than 18 inches high or so many obstacles in the way. But with the right height and limited obstacles crawlspaces can easily inspected. I would suggest a yearly inspection and that inspector can also mention things like:

• water pipes leaking
• air conditioning vents on ground
• sometimes under mobile homes they leave the wheels in place, these need to be inspected as well
• pillars (block or metal) checked
• insulation falling or loose
• crawlspace access points not sealed or in place, loose or non existent metal
• dirt falling in

Anyway you get the point, yearly inspections