I've got a Pioneer AVH-X2500BT, works with steering controls with the right adapter, bluetooth, works with my reverse cam, plays DVDs full of MP3s as well as movies (not sure this is that useful TBH ). Things I wish I'd considered when I bought it are:
The touchscreen is a little laggy, compared to say an modern smartphone, not sure how it compares to other brans of HU
Integrated sat nav - I'd prefer not to have an extra device in there
Digital radio (wish I'd got this)
Front facing USB port - wish I'd got one so I could do firmware updates and use USB stick without ripping the console out.
The second and third of the above can be worked around with an adapter for a smartphone and an unlimited data deal.
There's loads to choose from, so do a bit of reading as well as what comes up on here. Good luck mate.