The Bottom Line: In the price range this is an excellent head unit. It has all the features I require. It matches-up easily with available amps and speakers ( not finicky).

I bought this stereo to replace an Alpine unit that had been in my 1996 Toyota Tacoma since it was new. I finally just wore that one out. Alpines seem to be very reliable, at least in my experience.
The instructions come on a CD disc, which some people don't like because you must go back and forth between the vehicle and the computer. I just printed off the pages I needed (approx 4 pages). The manual warns about possible conflicts, like when you try to connect a VW antenna, for which you must buy an adapter. It mentions several other possible problems and their work-arounds.
The Din/ISO install was very straight-forward. The sleeve and trim ring just pops off. The new wiring harness is correctly color coded and comes with connectors.
Since I had a 2 channel (2 speakers) amp I didn't need to run new wiring in that area.
FYI. IMO you should try to match your amp to the speakers and use speakers with a built-in crossover. I plan to add 2 more speakers, when I do I will install an Alpine 4 channel amp. Speakers sound WAAAAY better with the proper amp. I will also install a capacitor for those times when my car alternator/battery might not keep-up.