This is a review of a cheap Pumpkin head unit with some nicer features like GPS and a decent amount of memory. The unit seems responsive and fast. The screen is not the brightest out of the box and has no obvious knobs to adjust it but if you go into settings (admittedly quite buried in the menus) then you can get brightness and contrast to be OK for daily driving. The sound output is great for my system (I only have two channels) but not sure it would be great for surround. Everything about this unit is cheap but not cheap. Actually, you do not need a manual - all the pinouts are available in the settings once you power on the unit. The wires are all labeled well (like speaker wires have labels) and the wires on my unit follow standard codes so, for example, my sound was good the first time I hooked everything up. Best of all, when I made a mistake and failed to properly hook up the reverse wire, their tech support spent two days with me by email helping me troubleshoot. It was slow but I have to admire the commitment to the customer.
I just installed the unit so I have no idea if the screen will last or anything to do with longevity. I also think that if you have a few hundred dollars extra and don't want the installation hassle then maybe buy a brand name and have the dealer install it. If money matters though, then this unit is an impressive bargain for the money.