If you could have one caliber..5.45 vs 5.56 vs X39

[ACC]

I just feel like 300 is only good for one thing..Kicking in doors and being sub sonic lol

Nah....it is great for that, but I hunt deer with supers and they are good out to 150 yards. Plus you can stretch it out to 300 yards for target shooting. But it definitely shines in suppressed 9" barrel configurations with subs.

 

[DadSmith]

I just feel like 300 is only good for one thing..Kicking in doors and being sub sonic lol

I'm a rifle guy as in 16" + barrels.
I reload, and I've been checking into the 300 BlkOut for several years.
If one reloads you can get better than 7.62x39mm performance with 125gr bullets, and I've seen my buddy take said combo out to 400yds hitting 6" square AR500 targets consistently.
I'm very interested in 300 BlkOut for deer hunting capabilites.
Plus the ability to shoot from 110gr - 265gr projectiles sounds like a lot of fun playing with different loads.