I'm late to the party, but my vote goes to the Burris XTR-2. Tough, well established by now, great prices. I've looked thru the 4-20 and 5-25, I bought the 4-20.
As far as the XTR-2 line goes, I don't know why some people don't like the glass, and others (including me) think the glass is great. I have decent 20/20 vision, and I think the XTR has great glass, especially for the price. It doesn't compare to a Vortex Razor Gen 2, but from what I've seen in the PST Gen 1 and 2, it's pretty much the same. I know that sounds IMPOSSIBLE!... But I'm being completely honest when I say I didn't notice a difference in glass. I've pretty much formed the unpopular opinion that all the "around $1000 scopes" have about the same quality glass. YMMV.
I grabbed my 4-20 for a sweet price, they've been out for a while now and since the PST Gen 2 came out the prices are better than ever it seems. I went with the XTR 4-20 because I never needed to turn my magnification up past 18x or so. Figured I'd save the dough. I also do notice that the image darkens and gets a slightly more fuzzy above 20x (but this is also apparent in the PST line for me) but it's still usable for sure. Honestly I don't think you'll be disappointed with any of the choices though.
Burris and Vortex have kickass warranties (I've used both companies warranties, but was very happy with the service both times).