The Barska's are nice low cost scopes. I've never had any problem with them at all. When I want a little better quality I buy a Swift, not cheap cheap, but reasonable and very nice for the money. If you need to replace the Nitrogen in a scope just get a can of the computer dustoff stuff, it is perfectly dry and will do a great job of clearing out you scope and keeping it that way. Biggest thing I find about the cheap scopes is that the adjustments are not as consistant as the high priced ones. On a Barska three clicks left may really be three clicks left and one click up, or two clicks left and one down. Just takes a little more time getting it sighted in. From my experience, once they are on target they stay that way. Larry