Unfortunately, as the thread just below yours notes, we have basically ZERO reviews of the new Viper scopes. There is one anecdotal report of somebody looking through the 85mm Razor and the 80mm Viper HD side-by-side at an optics fair, and claiming they were very close, but that's pretty much it.
Some things to note in terms of specs that do separate them:
- Razor has a wider field of view for the zoom eyepice
- Despite the larger objective, the Razor is more compact (2" shorter and a bit lighter)
- Razor has better close focus
So all of the above plus the larger objective probably means that the Razor, overall, is just slightly better in a few ways adding up to a superior overall package. The Razor's larger objective means, given equal samples, it should perform a bit better in low light and at high magnification... plus the zoom EP might be better (it is similar to the excellent Swarovski clone on the ZEN ED2) which should in theory add up to slightly better optical performance.
The above paragraph is unfortunately all speculation though... until someone gets their hands on one of these we won't know for sure! I really want to know how the Viper HD 80mm at $799 compares to the ZEN ED2 82mm. When the Razor HD was introduced it was the "king of the budget scopes" for those of us who can't afford alphas, but I really want to know how the Razor HD compares now too....