I'm currently in the same predicament. I just placed my order for my Colt SP6940, and I'm looking around at a couple of different options for low priced optics. The gun pretty much took up my entire budget, and I don't plan on using it to fight a war with, so Aimpoints and EOtechs are out of the question. The main purpose will be for plinking at ranges of less than 100 yards.
The two options I'm looking closest at are Primary Arm's M4 clone and Truglo's multi reticule open red dot. Not really sure if I would rather a tube sight or not. The PA M4 seems to get really good reviews, and the fellow that runs Primary Arms seems to be a real stand up guy. However I also like the smaller physical size of the Truglo sight, and they offer a lifetime warranty. Decisions, decisions...
The two options I'm looking closest at are Primary Arm's M4 clone and Truglo's multi reticule open red dot. Not really sure if I would rather a tube sight or not. The PA M4 seems to get really good reviews, and the fellow that runs Primary Arms seems to be a real stand up guy. However I also like the smaller physical size of the Truglo sight, and they offer a lifetime warranty. Decisions, decisions...