You've received an abundance of information here and obviously it's up to you at this point to determine what your needs/wants are for the compass. As Roger mentioned, and I agree with, a basic compass with no adjustable declination or clinometer is more than sufficient for navigational purposes.
While a very good quality compass, the US Military Lensetic compass doesn't have adjustable declination and hundreds of thousands of service men/women navigate just fine with it. By going with a basic compass, I'm sure that you could save 1-1.5oz compared to the ~ 2.5oz MC-2 which was my recommendation. Although, if you're carrying a mirror anyways, you'd have to factor that into the equation.
For backpacking purposes, 99% of my navigation is by terrain association and I rarely use the compass. Knowing this, I still bring my Suunto every time. I figure since I drink cowboy coffee and use Esbit instead of a canister stove, I'll allow myself this luxury.
I would recommend that if at all possible, buy your compass from REI or another vendor with a similar return policy. When I purchased my MC-2, I quickly noticed that the clinometer didn't swing freely and I'd have to jiggle it some to get the needle to settle. At the time of purchase/unboxing, I was unsure if I had a defective compass or if this was an issue across the board with this particular model. Fortunately 1/2 my SAR class had the same compass; I was able to determine mine was a fluke defect and immediately returned it.
The Silvas sold in the U.S. do have a poor reputation but I haven't used one since the '80s so I can't speak to that; there were none in my class. The guy who sat next to me in my SAR class had a Brunton (don't remember the model) and he was really happy with it throughout the course. Again, no personal experience with this brand that I can comment on.