It's the hair that will fail (fall out) long before the French base, and probably Swisslace, does. Gather your current base is mono which again is very durable and may or may not hold the hair in for longer.

Mono is what some of the big salon chains tend to use along with high density hair so it will take longer for it to thin down when it sheds. I was getting 6 to 9 months out of these at AHS. But the trade off is a thick base and thicker hair, crap hairline and no show scalp - i.e. loss of reality, plus a hefty pricing and time consuming maintenance visits.