i've owned 2 xls
the .25 i tuned up and got it running 'right' , it came at 8fp and after a tune it was 11.5 but the barrel wobbles in the breach and the barrels are so tight you could shoot it for long before you had a sore thumb. i had to use rhinos which turned out to be perfect.
the .22 one was equally as bad, i made it a .177 and it ruined it. could not get over 9fp. sold them both, wont buy another bsa springer again.