It really depends. Each model has various CPU's you can purchase it
with, so that and RAM will make a difference when compiling. HP does
mention specific support for Linux since the site I was on referenced
the HP 635 as a business model.
If I recall correctly neither unit has supported Graphics for Android,
but then again most units these days don't. (Accelerated Graphics)
Perhaps someone here can give an honest opinion as to AMD Vs Intel
when it comes to compiling and development. I know back in the day
there was a difference on CPU's based on the tasks you would be doing.
Don't know if that divide still exists.
Plus, it also depends on budget. If you can get a steal on an AMD/
Intel then it might free up your budget to buy a cheap netbook for
build testing. ;-)