If you're serious about getting into rimfire competition, talk with the person who runs the matches and get his opinion on what rifle might be competitive. You may be buying the wrong rifle in a CZ or other sporter, if the competition is using high-end target rifles.
Also, you might be able to borrow a rifle to try for a match or two. Competitive shooters are often happy to let someone use an older rifle. That's also a great place to buy one.