Leshiy

You'll like them both...!!!

Ok... What kind of advice...??? I have both... Others do as well I am sure... The 22/350mm is a laser, this rifle has a bit of a bark, I use a DonnyFL Sumo on a DonnyFL adapter and it tames it a lot, it's a hard hitter... The 177/250 is also a laser, not much to dislike about Lothar Walther barrels or the Edgun Leshiy… It's one of my favorite air rifles...

Ken
 
I have leshiy set up with 350mm .22 barrel and it is a lazer and has good shot count , I run mine at 91 bar reg setting with HUMA and get 23 shots at like 820fps



I will soon tune it 12fpe and see how it preforms for close quarter nite shooting , for me the longer barrel takes away harmonics and increases shot count , but either way gun is accurate and compact ,
 
I agree with the others that the 250mm barrel gets twitchy as you increase power. I'm running a .22 250mm barrel at 20fpe (JSB 16gr @ 750 fps) with the stock baffles and it's plenty quiet for me. Also very accurate and not too twitchy. If I bump up the speed to 800fps+ it does become a bit to handle. 

Now I also have a .177 350mm barrel that I run with the DonnyFL 350mm adapter and a Donny Tatsu. It's set for 10.34gr @ 900 fps. So approx same fpe as above but much easier to control.

Here's my take on the 250/350mm barrel debate. If you want to keep the Leshiy small use the 250mm barrel. If you don't mind it being either longer or louder then the 350mm barrel might be a better choice.