I have owned an s400 classic .177 for five years now, its as new still, and shoots superbly. Mine is standard, but i have polished the hammer rail inside and bolt to get rid of slight machining marks, it cocks and fires so smooth. I would suggest you find the sweet spot on your rifle, it really is worth doing although a little boring to do. I fill mine to 155 bar which gives me 44 shots down to 125 bar which are more consistent than any of my regulated rifles. ENJOY.