I have put about 1500 shots through my RWS 34. This gun is real accurate and fun to shoot. On calm days I can shoot 1/4" ctc groups at 20 yards 3/8" groups at 30 yards and 9/16" at 40 yards.I am just inclined to shoot my D34 in stock form until the spring and seal go out, then I will build a spring compressor and install a Maccari or Vortex tune kit.My question: How long can I expect the stock spring and seal to last?