Very much depends how long you're in the car for, whether you actually listen more to cd/mp3 or the radio and will you even use the multitude of facilities or gadgets that are available.
If it's mp3s then a cd reading one may well be enough, or a dvd reading one at 4.7Gb each is an awful lot of tracks on one disk alone.
Aux audio in may be enough, maybe with an ipod connector, or a simple lead to any player.
I recently got a motorised monitor unit that does just about everything, ipod, usb, sd, dvd, tv etc etc etc, but realistically, with a dose of hindsight, it's only the radio i use more than anything, and the aux in for an ipod controller. The rest is nice to point at and play with yet rarely, if ever actually used as all the different multimedia input is all good and well but how many different ways do you really need to do the same job?
That aside i'd stick with the main names, jvc, kenwwod, sony etc are all listed on the site you mention at well under £100 which may not list as many goodies as the lesser known and often chinese brands, but will be of a known quality and durability.