the replicator clones (what wirlky recommended at the bottom of his post), while excellent machines - don't have that great a build volume. 225x150x150 (pretty much any printer with that build volume is likely to be a replicator clone)
Of the three printers you listed I'd go with the original prusa i3 mk2 - for the same reasons wirlybird mentioned.

As far as printing faster with a larger nozzle goes, not neccessarily. It depends entirely on layer height and print speed. All the nozzle diameter does is determine the minimum width of the bead. So for finer horizontal detail a smaller diameter is usually better.
Like all things - up to a point :-)
My advice is to start with the 0.4, it's easy to change and buy different diameter nozzles. So start witht he industry standard 0.4 and change when you feel confident in the printer and how it works.
Also there are temperature and cooling issues with printing with large beads.

As has been mentioned, unless you have an enclosed build volume, abs will not only be a real pita to print, but weaker then pet-g or pla. Unless the whole model cools at the same time there will always be serious layer adhesion issues.