From what I've been reading the main difference is simply exposing the TRIM command, which can in no way be a detriment - the only reason to disable TRIM is to hide the fact that it's SMR
But, why would failure to expose TRIM cause errors in in rebuilding a RAID, in which case old drives should be more or less read-only, and replacement drives write only? My understanding is that TRIM should affect re-writing sectors only.
I don't see why RAID rebuilds should take notably longer on SMR drives, if only they were properly managed - by both the RAID driver and drive FW. Though it's hard to properly utilize a DMSMR black box.