X3. I have the short LW barrel on my .177. It is absolutely dog nutz out of the box. I got a new pin from the dealer, fitted it in 10 minutes (literally) and voila, took her from a 430 ish fps ***** cat to a 940 fps bruiser. One hole at 50 yds with JSB Exacts all day
I'm only 50 mins from a dive shop so it's not too bad. Almost everyone I know who has bought a pump has got ticked off with it real quick. It's LOT of work apparently, particularly at the higher pressures.
Cheers
DaveD