Back when you could get Veprs at 500$ they were the best AKs on the market. Now that Veprs are 1000$ they're still the best AKs on the market. That should tell you something. When you handle them, look at the way the BCGs are machined, the thickness of the barrel, the way the recievers are made, the way the selector snicks off properly without too much effort, the straightness of the sights... they're just better than pretty much anything else that's out there in the stamped field. The only thing that really compares to a Vepr is an Arsenal milled gun, assuming you don't mind the weight, and if you do mind the weight get a SLR 104 or 107. Those are great guns as well, they're well made and have all of the modern features (plus you don't have to work on them to configure them like a military rifle), but the overall fit and finish is a grade below the Vepr.
Saigas are not bad, they're just too expensive compared to comparable AKs on the market. Unconverted Saigas are the price of Yugo AKs, which are just as nice, and converted Saigas are 30%-40% more expensive than Bulgarian SLRs. If you want a side-folding SGL-21 or 31, prepare to pony up Polytech Legend amounts of cash. They're just not worth what people are paying for them, but they're doing it because of the percieved rarity. I remeber when they ran around 580$ for the SGL-21s and about 700$ for the SGL-31s, my LGS had a SGL-31 that they just sold for 1900$. Veprs on the otherhand came in the country around 500$ for slant backs, 650$ for straight backs, then after the ban they shot up to around 750$ and have been creeping up ever since. Given the quality levels and what the Veprs I own mean to me, I wouldn't part with mine for less than 1000$ each, that's just what I think they're worth in terms of comparable quality.