The Elcan C79 is not bad for what it's designed for, but definitely would not be my first choice for anything.
It's designed to be used & abused by an infantry grunt, and it takes that abuse quite well. It is clear, with a nice wide FOV, and the tritium insert is a great feature for low light shooting. However, in my opinion the C79's list of drawbacks is a lot longer than it's list of advantages. It's heavy, the adjustments only work like they're supposed to SOME of the time. It's "battle sights" are a joke, and it is easy to strip the plastic "knobs" right off of the screws on the base.
The Spectre DR is also not a piece of kit I would ever buy. Never mind it's ridiculous price tag, it's unreliable. It uses a base similar to the C79, but that's not the problem. The problem stems from the 1-4X flip switch. I've used the Gen 1 & 2 models, and with both, we've had a number of sights in each batch that had problems with returning to zero. It's a difficult system to perfect; flipping an ocular tube back & forth 90 degrees & expecting it to be perfectly lined up every time. The majority of the scopes that I've seen held their zero fairly well (for 20-30 flips) but some would put you off the paper after one switch. Because of that, I can't trust the rest of the scopes, because who knows when they'll start to slip?
Another problem with the Spectre DR we noted was a change in POI when switching from 1 to 4X. This was not a problem with a few scopes, it was a problem with ALL of them, but to varying degrees. Some scopes would notice a change as small as 2MOA when flipping from 4X to 1X, others as much as 8MOA, but not one of the Gen 1 scopes was without this problem. The Gen 2s are fairly consistent at a 2MOA shift.
My $.02
Cheers.
Tim