I've got a Tasco Propoint 3 on my Smith 41 that has been there working flawlessly for over 12 years now. I shoot a lot of Bullseye, so it's a frequently used item that just flat works. I have had three of that same make and model sight go bad while on my .45 though, and that pistol now has an Ultradot which has been working fine for a few years. I think the Ultradot is a better option here and would suggest that a new purchaser go with that over a BSA/Tasco/Simmons/etc dot sight. The Aimpoint is good stuff but costs more, and the Gilmour is in that same boat. Other dot sights like the C-more are a different animal and I don't have enough experience to comment on them.
I use a Kowa 821 as my spotting scope for Highpower shooting. It's pretty much the standard in that field and I bought mine because it's what every body else had, or was trading up to. You do need a strong stand for it though.
I've got a mix of low and mid price range riflescopes on some of my rifles, and I like the Sightron S-II fixed 24x best so far. I use it for Silhouette and it's clicks are very consistant. Another scope, a Bushnell ScopeChief, has good optics but the clicks differ sometimes so it's better for something that will be sighted in at a single distance and used without constant adjustments. I also have a mix of Tasco, Bushnell, and Simmons scopes that I switch around on .22s and shotguns (the low powered ones with good eye relief). They are inexpensive scopes that will work when there is good light on a nice day, which is when most people use them, so they're not too bad for the money. I do have a Leupold Vari-X III in 4-12x, and an older Vari-XII in 2-7x that are very, very nice scopes, probably my best pieces of glass. And a Weaver KT-15 that has been on just about every rifle I have at one time or another. For the money, that Weaver is tough to beat, it can do just about anything.