quote:

Originally posted by sambarman338:
I don't know anything about the quality of the glass or coatings but I do know there is a vast difference in the erector-tube springs.

The Z3 uses a conventional flat spring at the front end of the tube while the Z5 and Z6 models use four small helical springs behind the rear end.

Though the Z3 spring has a small ball on the free end to limit its chattering against the outer tube when taken to the extremes of adjustment, the helical springs should obviate this problem altogether. Swaro didn't mention that aspect on their website when last I looked, though, saying instead that the coil springs behind the erector tube were to cope with recoil inertia, which they say can be 500 to 800 times the weight (if that's the word) of the tube at rest.