We retired our KDF-50WE655, purchased Oct 2004, to the game room...but it is still used almost daily since we prefer it over both of our Mitsubishi's for PS3 gaming. I can't say one bad thing about the set; I am still using the original lamp with probably 5000 hours on it...along with a spare lamp I received from Sony.
My 11 month old Mitsubishi Diamond DLP (WD-57831) already burned through a lamp last month (2400 hours) and this past weekend the light engine fan stopped working. So far, my experiences with Sony have been fine (haven't needed any repairs) - both Mitsubishi's needed warranty repair...as did the Samsung.
As such, I have no opinion regarding Sony service; I spent weeks trying to find someone in my area to service the Sumsung, but I will say the folks at Samsung stepped-up to the plate and replaced the set at no charge; the Mitsubishi sets have a lot of nice features, but their DLPs break far too frequently...and also seem to wait a long time for parts. Personally, I cannot recommend purchasing a current Samsung or Mitsubishi DLP...unless you get a really good price and a matching really good extended warranty that included two lamp replacements. Anyway, I was really hoping Mitsubishi would be releasing their new Laser DLPs this spring, but they won't hit the streets until 4th quarter. Additionally, it appears the 65" model will be priced in the $4500-$5500 range...a lot more than I am willing to pay.
Yep, there is a lot of bashing of many of the current sets...well, the technology in these HDTVs (i.e. light engines) just hasn't turned out to be nearly as reliable as the good old fashined CRTs. To be honest, most new appliances such as washers & drivers and refrigerators just don't last like they used to. We keep a spare 22+ year fridge and washer & dryer in the basement...and we just replaced a 4-year old washer (heck, had to replace the dryer too since my wife wanted a matching set) and 8-year old fridge.
I am not a fan of the extended warranty, but I would recommend purchasing a 5-year bumper-to-bumper warranty with your next big screen purchase. I purchased my last set from a local higher-end retailer (thebigscreenstore.com). They are typically a little more expensive than the local Best Buy and Circuit City, but they have a half-dozen really good sales each year in which they bundle many of their sets along with a premium 5-year warranty (two lamp replacements). Believe it or not the price was actually cheaper than BB/CC and just about every internet retailer out there. Plus, whenever I have a problem...I just call Ted and he takes care of the rest (no sitting on hold with Mitsubishi or some warranty company). Currently, they are selling a WD-65833 w/5-year warranty for $2899.99 and zero percent financing from Mitsubishi for 16-months. Dollar wise, this is a pretty good deal if you can get a price match in your area.