Been debating between the Polonium or Polonium K for my 10.5" SBR 5.56.
I already have a Rex Silentium 358 K (9mm rifle rated can).

I meant to buy the Polonium K, but must have messed up my cart and bought the full size instead.
When I realized it at first I panicked but then I thought this might be for the best.

I definitely value suppression, however I love to also run simple guns.  I have an H3 buffer in there already, but don't really want to change out my barrel/gas system/BCG unless I have to (it's a 10.5" with the KAK Mini Milspec Buffer and 3.3oz "Heavy" buffer option, no heavier options).

Did I make a terrible mistake and will be dead from the gas in a week?  Should I try to cancel it and get the K?  I really value suppression but hear the gas is really bad.

I got to demo a Polonium recently, it was pretty gassy. Sounded really good though.

This helps 100% with both ways I'm leaning LOL.

I think I'm going to keep it, why get a can if it's not as quiet as possible?
My Rex does decent (it's hearing safe but not by much, definitely would be fine for self defense or hunting without ear pro).
I guess this will give me a good option between my two cans though my Rex now lives on my Stribog.

I have a full size on a 14.5 middy, 0.074 gas port, A5H2 buffer and M16 spring. Thing gets noticeably gassy very quickly. I’m thinking it’ll get moved to a 243/6mm arc bolt gun once I can afford to put a CAT WB 718 on my 14.5.

Buy a BRT EZ Tune gas tube.  Give them all the info about the can and your rifle. Let them choose the best port size.

https://blackrivertactical.com/WP/BRT-EZTUNE-Gas-Tube-Configurable-Carbine-p103167251

Give it a try and see how you like it. The gas tube is easily replaceable.

I like the full size Polo a lot, but I only use it on a suppressed only heavily tuned SBR.  I never understood why people don't want a tuned AR for maximum suppression (unless it's like your only AR or something). I have some that are tuned and some that aren't. I use different cans for each.

Pretty gassy, you need major tuning. I have a Polonium on a 16 inch midlength barrel. Even with BRT EzTune 0.067 tube and A5H2 buffer, gas was enough to irritate my eyes. After I switched to a KAK K-Spec down vent BCG and upped the buffer weight to A5H4, the majority of the gas was gone but mag dumps will still cause gas buildup.

Mine isn’t gassy at all but I’m shooting it on a LMT piston gun.  But I don’t remember it being gassy on my 18” SPR either.

Not bad on my tuned 11.5/16/18" guns. I run a SA BOGB, Sprinco Blue, Silencerco CH, and H2. I only notice gas when rapidly ripping off the rounds.