These guys nailed it. $20-25 is a tough price point for quality domestic cabs; not impossible, just tough.
Here's a few that are decent:
- Beringer Knights Valley (Especially '10)
- Justin Cab
- Arrowood Cab
- Freemark Abbey Cab
* Note that these won't touch Caymus in terms of quality.
When & if your wine hobby drifts to Spain, Italy, or the Southern Rhone, I find a ton of better QPR wines in the $20-30 range. In the mean time, get out to some local tastings if they're available.
Cheers, & welcome.