I bought my 2006 from a guy on eBay who said that everything that could be done to this radio (mods and upgrades) had been done and it was a hotrod. I didn't really care that it was a hot-rod, I figured I would never use half of the mods anyway (cellular, not interested...discriminator tap, never use it, squelch tone was ok...SSB if and when I use it, probably never...now the backlight mod is nice, brighter, and the scan speed is nice, faster...and it goes up to 1300mhz...so what....some other stuff he listed I will never use or ever verify) .Once I had checked the scanner and took it for a spin around the block and kicked the tires, I gave him an excellent feedback for fast shipping, and got what I wanted. It was a mint Pro-2006 and it worked flawlessly for what I needed it for - a good scanner dedicated to conventional frequencies with decent sensitivity. I don't care about all the bells and whistles on an older scanner that are standard issue on newer scanners today.
IMHO, this scanner has always been King Tut in the Analog Empire. I use it for a lot of different things because of its sensitivity - milair, railroads, itinerants, local business, FRS/GMRS and it gets the hits sometimes better than my other scanners on the same discone antenna on the roof. I have switched it to the directional yagi but it seems to fare better working Omni-directional with the Diamond Discone. I will never sell this one, it's definitely a keeper and a fine addition to my station.
This is silly, but the real reason the 2004 caught my eye back when it came out is because it resembled the MDTs (Mobile Data Terminal) in police cruisers with the multi-colored membrane keypad. I know I know...it's a geek thing