Which Reflex Or Red Dot Sight For My Browning Buckmark Sporter Rifle?

Of the links you provided, I'd go with the Ultra-dot. IMHO BSA is junk. You might also consider the Millet 3 moa which is about $100 at Natchez. The Leupold/Gilmore 1 moa scope would also be a consideration.

Ultra-dot

Personally, I like Aimpoints the best, and will save up to get (another) one rather than buy a cheap one.

I tried a couple the "heads up" type sights like the ones in your first couple of links and never could get to like them. I always felt like I was looking for the dot or reticule and then for the target. With the Aimpoint or "tube" type sights, I just look at the target as the gun comes up and the dots right on it as it shoulders.

I know lot of people badmouth BSA, but I've got one of their $40 30mm sights that I got to see if the dot sight was what I was looking for(and boy was it! ) and its still going strong. Its been on everything from .22's and .223's to .308's and full auto 9mm SMG's. If your not sure about what your looking for, it might be the way to go to get an idea. I think Midway has they for about $35 or so now, and you may find them for less on sale. I also have a BSA 2x pistol scope that I got for free when I bought something off CDNN. I used it on my SOCOM as a Scout scope until my Leupold got here, and shot the crap out of it, and its still fine too.