I've never shot a rifle equipped with a Slidefire. But, I have had some brief trigger time behind a full auto (legal, w/auto sear) AR.
Any rifle, and most pistols save for the Kriss, are simply uncontrollable due to muzzle rise on full auto.
Many FA rifles are more controllable than that statement portends.
Spend more time with full auto.
On a few occasions, I had time to "dispose of" old ammunition while I was serving my time.
Using an M16A3 borrowed from a sister unit, I qualified for 'Expert Marksman' status ... with the rifle set to full auto, and a test procedure (and target) that's designed for semi-auto-only slow fire.
My score with full auto was actually
better than what I was ever able to achieve with any 3-round burst variant of the M16/M4.
Many platforms, particularly small caliber platforms (5.56x45mm, 5.7x28mm, and 4.6x30mm in particular), are quite tame once you get to know them.