The debate is over and drives win.... But we can still rebuild 40 year old generators but now it seems when drives go obsolete the majors are no longer engineering retro fits and software updates....customers lose..
From what I've seen is original OEM drives parts are available. It's when the OEM's went to 3rd party vendors (Allen Bradley, Robicon, Louis Allis, Baldor, etc) is when obsolecense comes in the form of the 3rd party vendor deciding to obsolece a drive.
Maybe the one exception is Magnatek with the DSD 412 and the HPV 900. Both been in production for about 20 years and are in use by multiple elevator companies. Of course that was after Magnatek absorbed Louis Allis, and Robicon.
From a repair standpoint, I'd much rather carry an SCR to the machine room for replacement thant haul a 2000 lb generator up and down the stairs. Oh my aching back...
