I taught different safety at sea courses for the better part of a decade, some included pool work with inflating life rafts. Out of the couple dozen class inflations through the years, I think I saw 3 different failures or partial failures. One tube valve, upper tube and canopy leak and one failed to inflate past about 20 percent.
Pretty high percentage rate....plus all the inflation failures of USCG equipment though the years in actual emergencies....makes me wonder and wary.
So many times you hear people here on TF say that they had to go back and fix things others have fixed for them......hmmmmmm....liferafts probably have a better QA than many businesses, but there are still plenty of failures. Not so sure I wouldn't trust a repack if I learned the proper way and did it myself....