I shot several hundred rounds of the old Federal Nyclad .38 Special when it was available and it was my carry ammo of choice for my .38 wheelguns. It was accurate and didn't lead the bore like the lead .38 LSWCHP did. I don't recall any negatives to using them.
I'm carrying the blue Nyclads right now, buy all the old stock I can find. Have it in .38 Special, .357, and 9mm. It is good clean carry ammo (no lead transfer to hands, clothes), but I would not waste it at the range, is very pricey.