The only thing I can remember that is sort of negative was a job where cube tests of the grout failed early on. We had the contractor remove and replace them. Well how?
He drilled right down thru that weak grout and did the job again at each pile. As I recall only about four of them had been done at the time, for a power generating plant.
Later load testing showed them to be OK.
Otherwise, the main concern I have for these is being able to penetrate obstructions, as a driven pile would.
This type of pile probably requires more in the way of pile load tests to prove their worth than driven types. This, then is a test of "settlement" I suppose.
If in doubt as to suitability of the pile for the job, some trial installations, ahead of time,before bidding has been done, generally where a grout pile contractor wants to show his pile can do the job, so he can be allowed to bid. In these cases, be aware that you need good records of all parts of the test,since it may turn out that there is a claim later due to "unforseen conditions, etc."
That's where this business of obstructions comes in. No one wins when a whole week is spent in arbitration to resolve the problems that develop.