Have owned the above scopes for several years and have found these to be top performing in the relative price range. In fact I don't realy like using anything else. They both hold excellent zero and are strong waterproof and rubust and have recieved heavy hunting abuse .
I now own an MTC Viper alongside the SR12 , the MTC is a class piece of kit, but if I'm perfectly honest at high mag I dont seem much difference in the glass between this and my SR.
There seems to be a a bit of an anti Hawke bandwagon kicking about, this Im sure is justified be several of scopes Hawke make, all I can say is that the SR scopes are quality and the reticle should be applauded not ripped to pieces.
lets face it everybody is after the MP20 (?) reticle on the MTC etc. Same idea, however i find the SR easier to read and clearer in low light level shooting (might just be me).
As many have said, try a scope and make your own opinions The beauty this forum offers all its members is that you can buy kit try it and sell it if you dont like it without loosing a fourtune. most times just the postage.
SR's get the big thumbs up form me The MTC Viper is also a great piece of kit.