I am building a new AR-15 and want to get a red dot sight for it but need to stay cheap. I have two other AR's with EXPS2-0 with G33.STS Magnifiers on them and really like them a lot. I'm looking for something under say $150 that will do the job. This will just be a backup and target shooting for fun gun and of course if I need to can always swap out the Eotechs from the other two. Any advise on what would be a good cheap red dot to get?

Primary Arms

Alternatively, TRS-25 are good, I also kinda like the Burris Fastfires but they're a bit out of your stated price range.

Thanks, I went with the Burris FastFire™ III which is a little more than I wanted to go but  lot less than the Eotechs.

Just put a Bushnell TS - 125 on an AK and it's incredible for the money !