You are jealous because both mine and Daves Sonys work perfectly (and mine has the best SDTV picture I have seen!) 
Me? Jealous? Of Sony junk? Never. And I know you're lying, as the last Sony CRT with a decent picture would now be so old the tube would be way past it.... 
It's only 7 years old so has a few years yet
Under general use (1.5hrs per day, 6 days per week average), a CRT is said to be at end of life at 5yrs. Due to the default settings Sony use on Wega sets (Brightness set to 100% - this and high contrast make it look good in showrooms), this is significantly reduced. I would have to say, its probably way past its best. Not worth changing until you can find a flat screen you like though.
Firstly it is not on LIVE sear eyeball settings but with brightness reduced - I found LIVE unacceptable for use
It is also used quite a large bit of the day - either childrens TV/PS2 16:00 through to 22:00 to 00:00. I have seen worn CRTs and mine is not worn - no screen burn either. THat said it still looks better than most Plasmas and LCDs.
I have run a setup DVD on it and one of my favourite parts was the sharpness chapter.
No matter where it was set you could see all detail with no ringing - isn't RGB wonderfull
Video Essentials I think