I just picked up the NDS rear sight (and front), the quality is outstanding. I was looking at both the Tech Sights and the NoDak. I ultimately went with the NoDak because I wanted the ability to mount an optic like the Burris TRS-25 Micro Red Dot in the near future and have it co-witness the irons.
If you don't plan on ever using optics though the NoDak Spud's integrated rail is moot.
I just picked up the Tech Sights TSR200 set up, easy install, they seem tall on a stock 10/22, but I don't have to squat my head so far down to look down them like I do with the pumpkin post sights. I haven't tried them out at the range yet, will do soon, just picked up some ammo.