I have an AAC Element II and Silencerco Sparrow II - just a few observations:
1. The Element II has NO first round pop on pistols or rifles (I hear stacked baffle designs tend to have less tendency for a FRP).
2. The Sparrow II does not have a FRP on my rifles, but DOES have one on my pistols - apparently the extra barrel length slows the gasses enough before they hit the silencer that there is no FRP on the rifles.
3. The Element II is lighter and smaller - that coupled with the fact that it has no FRP means it spends most of its time on my pistols. My Sparrow II spends most of its time on my rifles where the extra size & weight are less critical.
AFA cleaning, conventional wisdom says the Sparrow II is easier to clean, but after cleaning both, I may be willing to say the Element II is as easy to clean, especially if you have a SS tumbler.
With the Element II, you can just toss everything (but the outer sleeve) into the SS tumbler - you cannot toss the Sparrow II into the SS tumbler without possibly damaging the threads and end cap, since both are permanently attached to the monocore.
Of course, I doubt I'll ever clean them that well again. The only reason I cleaned the Element II to "like new" was so I could try the silicone dip treatment.
They work better if slightly dirty, so future cleanings will probably consist of nothing more than the ultrasonic cleaner (Gunslick / RCBS).
FWIW, I cracked them open for their first cleaning at the 1,000 rd. mark, and mine looked nowhere near as dirty as pix I see of some folks are cleaning at 200 to 500 rds - don't know what kind of dirty ammo they're shooting?
After dipping both mine in silicone, I don't plan to crack them open again until the 2,000 rd. mark.