First, the pic you see is not of this head unit. See cardomain's picture, that is the correct one. The one feature that sold me was that there is only one knob, and it's on the left near me when I'm driving.
I've had this head unit for over a year and a half now, and I've taken home three trophies at SPL Competitions (Sound Pressure Level); that's what this head unit is meant for, fully customizing the equalizer curve to your preferences and/or competition specs. The price was right for my purposes, about $250 at Circuit City in the Spring of 2006.
I love this head unit, it's the baddest one I've ever owned, it does it all. Three RCA outs provide for a perfect configuration.
Do know that you have to buy additional cables/adapters/modules to make the Ipod and sat radio interfaces work. I got a Sirius interface and it's seamless, $100 retail but I didn't pay that much. Sat radio data appears right on the head unit display, and you can preset 18 sat radio stations, on top of the 18 FM stations.
If you do buy I suggest putting a coat of clear fingernail polish on the knob, it will start flaking after a few months, esp if you remove the faceplate frequently, that's why not a 10 rating.
This unit is built for competition and or those that prefer to tweak equalizer settings, not for mass consumption. Can't say enough that single left side knob was the clincher among competing, and more expensive head units.
My recomendation: this is ideal for people who have an iPod and/or who use iTunes. It will not only play regular audio CDs, but also your iPod (if you get the CD-IB100) and CDs that have mp3 and AAC files burned on them. (AAC is Apple's proprietary digital music format and music downloaded from iTunes is in the AAC format.) For general radio and CD use, there are other players with better interfaces.
I bought this product specifically because it can be hooked up to an iPod adapter (Pioneer's CD-IB100). That way I can get a direct line from my iPod to my car's sterio (as opposed to using an FM tuner for the iPod which has reduced sound quality). The sound quality is excellent for radio, CD's, and the iPod (using the CD-IB100). Yes, you can navigate through your iPod's menu's (i.e. locate music by Genre, Artist, Playlist, Album name) and select what specific music you want. This is because the DEH-P7700MP sterio player has an interface specifically to read data from an iPod (if you also install the CD-IB100). However, maneuvering through your iPod's menus from the sterio player's controls is slow.
One downside is that the sterio player is complicated to use. In order to accomplish certain functions, you have to navigate through several menus. It's not real intuitive, so you have to get the manual out and play around with it in your driveway before you attempt to do this while driving. For example, pausing your music should be simple, but involves several button presses.
One caveat: please note that this product will NOT play protected AAC files burned onto a CD. (Obviously it will play them if they are on your iPod and you use the adapter.) When you download songs from iTunes, they are saved as protected AAC files. In order to play those songs, you have to play them on a device that is authorized by your iTunes account. Your own computer, as well as your iPod, are already authorized. But, for example, when you try to play your protected AAC files on another computer, iTunes on that computer will prompt you to put in your password to authorize that computer. I.e. the protected AAC file has your account's name attached to the file, as copyright protection. This sterio player does not have the ability for you to authorize your music. So, if you insert a CD with protected AAC files, it will say "no info". Only non-protected AAC files (the one's you originally imported from your CD's) can be played in this CD player. So why even bother using this feature? Well, AAC files are compressed and take less space. For example, I can put 6 Metallica albums (I own their CD's and imported the music into my iTunes library) on one CD in AAC format.