TBAC, don't look back. I like the Ultra 9, damn quiet. Probably the single quietest suppressor I have but that one is 6.5G only. The 5" is nice too (especially on an SBR!) almost like nothing at all really it's so short and light, but it takes a .300BLK down to manageable levels. Over the years I've gravitated to accepting less suppression for less weight and length. But if I need it quiet, I have that too. The thread over mounts are just like using a direct thread but better. Seriously, this is where you want the mount and not the thread on. Those little brakes work too, never used their flash hider. It looks short but I'm sure it works fine or they wouldn't make it.
IMO, if you can deal with 7" then 9" isn't that much different but is quieter --and if you really need it short, go short. But to each his own, the Ultras just kick ass. They can take a fair amount of use in 300BLK too, wanna say they told me 5 mags at rapid fire was the limit. I haven't just pissed through 150rds. without looking since my last spendex 14 years ago though so it's not an issue. And if I have to dump five mags in the real world, I probably need to break contact.
I considered the Surefire but in the end said "fuck it" and went with a KAC QDC since it was going on an SR25 anyway. QDC is a never mentioned can that is actually very nice, one of the best QD cans on the market. It's fairly light, works well, indexes TDC each time, ratchets on and off with the twist of the wrist. Don't know what they do to .300BLK yet but they tame .308 right down to the sonic crack. There's an FDE one for sale on this site for an excellent price, $1100 (if you're gonna get one, that would be it, usually $1500). But KAC's mini version of this can is loud, just a moderator and I'd shy from it --never seen a bigger gap in performance from similar cans than between these two.
Good luck, all the ones here and the ones you're looking at are all good ones. If weight and quality are both an issue though, only one mfg. as far as I'm concerned. You say you'll use it on one rifle, pretty sure that'll change. You may wanna start looking at .22 cans because pretty sure you'll want one of those too. Sico is giving one away right now with the purchase of, say, a Saker; buy from Capitol Armory and they'll give away another on top of it I think. Good sales right now.