SVU. I don't even like being a sniper, preferring shorter/mid-range gunfights, and I think the SVD is both better in-game and "cooler", but I just love using the SVU. I think it's because you're likely to get an SVU long before you can get an SVD, so I'd often end up using one far more often then I would an SVD and got attached to it. It's surprisingly effective at a typical assault rifle or slug gun range, never underestimate the sheer power of 7.62x54r; it'll drop most humans in a single hit, and even chimera don't take long to dispatch.
When playing CS TFW, I found one very early on, before I had even joined a faction. My main weapon at that point was a Mosin. The SVU was honestly less effective for my purposes; it's scope had far too much zoom compared to the mosin's scope also fuck TFW for using a modern scope and rails instead of a PU scope for effective combat at shorter ranges, it was less powerful and had more recoil meaning I'd be both more likely to need a follow up shot and need more time to line up a follow up shot. I used it anyway, because why the hell not, and came to love it. Now I use it whenever possible when doing a run of any of the games, even though it's much less cost-efficient than in TFW. Mosins were so common, I'd have stockpiles of hundreds of rounds of looted 7.62x54r.