I take it that this is a new set, or else you wouldn't mention warranty. The cost of DVE is at an all time low, about $12. It's a good investment that will serve you well when you do get a digital set. For that money, and those prospects alone, I'd pick it up. If you want to spend even less, you might try to find a copy of plain old Video Essentials, the precursor to DVE, made expressly for TVs before the digital revolution.

From what you've described, I don't think that you have much to lose in asking a tech to examine your set--assuming a free visit (on Panasonic's bill). If the set varies from Panasonic's specs in a way that a technician can easily fix in the service menu, or if some electronic part has failed, you'd at least stand a chance of getting back into the ballpark. But if the gray scale and colorimetry are shot more fundamentally, I wouldn't hold out much hope, even if the store is willing. A change in the red, green, and blue guns probably won't do the trick. To get the color of grey right requires a good color analyzer, skill, and time. Most bread and butter TV repairmen don't have the tools, or the inclination. Maybe the store will let you do an exchange (hopefully, not all Panasonic analog CRTs these days are infected with the same disease). Without seeing the set, I wouldn't know, but you might have to wrangle with someone about what constitutes "broken" or "replaceable." I've seen Panasonic's recent digital direct-view CRTs, and they look good.

Ed