I have spent many many hours over the last couple years obsessing over optics, spending money here or there on various brands lines and trying them out, researching forums, reviews, mfgs websites ect...i still lack much in the knowlege dept, but it seems some good advise is given here. You might get lucky in the sub $300 range and there are a couple so called "gems" in that price range but it seems those are the exception, not the rule, and even the good ones in that price range are not 'that' good. There are a lot of people that do no know what a quality optic is. I started the game buying cheap stuff. Barska, some no name used scope, super low end bushnell ect... I do not have any of those scopes any more. Then bought a Nikon monarch UCC, trying to still budget and got an old 3x9 Redfield from my dad. For various reasons I probably will not retain these scopes much longer either. Fwiw the redfield holds zero but has a horrible yellow tint to the image, the Nikon has decent glass but am not convinced it reliably holds zero, and you cannot trust the clicks to be true to their values (i have also read several other accounts of the same click value issue with others that have various nikon scopes (i am aware that some scopes need to settle into place after adjustment, and i still cant seem to figure out what the heck is going on with this one)
Then I found a great deal on some Weaver Super Slams, a Vortex Viper HS LR (a better scope and glass than the basic viper line, but almost the same thing as the Viper PST eg; same glass and tubes, no illumination and the turrets have different adjustment click values than the pst's) and a Sightron SIII. These are all terrific scopes that i wont sell.
I did have something break loose in the Sightron which was rattling around inside it, Sightron happily and very quickly fixed the issue for free, also told me that was a very strange and unusual thing to happen. Of those scopes the sightron has the best looking picture. Very bright and colorful high contrast and sharp. The vortex and weavers i have are not far behind, but they also costed me signifcantly less. I would highly recommend any of them and there are some great deals to be had on the Weaver Super Slam lines especially if you dont get the Tactical versions.
My findings are also that you will pay significantly more for scopes in a given line that have the tactical features like illumination, custom turrets, ballistic drop reticals, side focus, flip up covers ect... The basic versions without all the bells and whistles are sometimes less than half the cost for the same basic optic. in other words, same glass, tubes, coatings ect... As their more expensive brethren. Some serious deals can be had for great glass if you are willing to sacrifice some of those features.
Another bit of advice dont buy based on warranty alone. And dont trust what mfgs say about how great their scopes are on their websites. People rave about Leupolds warranty service, i have never used it but my dads experience with them was not good. So dont count on that kind of thing. For that reason i have not been keen to buy any more Leupolds although they do have some decent stuff. And a couple of nitches no one else has filled as a mentioned in a recent thread. They are good, but not as good as some will have you believe (optically, duribility ect..) and as mentioned it definitly matters which line you buy from. Most brands are not excelent all the way across the board and Leupold is no exception to this. After all a good warranty doesn't do a dang bit of good if you need it working on a hunting trip or out in The field and it busts anyway. Nothing can make up for a missed oportunity or worse.
So thats my advice. Weaver has some terrific value in their Super Slam line, so does Vortex in their Viper HS/ HST/ HS LR lines. But glass quality matters a lot to me. Much more so than other fancy features. That being said i I just pulled the trigger on a Schmidt and Bender Zenith 1.1-4x because i finally found the sale I have been waiting for (this was after months of debate between them and others like the Vortex Razor or Swarovski Z6 ect..) I wanted to see if buying something truly high end is really worth it to me over something pretty good that gets the job done well. I will probably post in a couple weeks and report on it. It also was intended to be the last scope i ever buy in that purpose catagory but i doubt that will end up being the case. We'll see. Good luck.