Looks like ABS starts at 215 http://reprap.org/wiki/ABS
I print PLA at 210 and ABS at 230. I was printing PLA at much lower temps previously but had very poor part strength and layer adhesion.
There are some variations between different printers on what temperature is measured at the temp sensor versus the actual temperature that the filament sees (some of which is also affected by the feedrate) – so you should use the published temperatures as a guidelines, but be prepared to adjust up/down for your particular setup. In addition, different additives and colorants will change the characteristics of the plastic from that of the base plastic.
Creepy
One other suggestion for the neck printing issue, have you printed the single wall object calibration? I didn’t notice trouble on some of my prints until to details where fine, and then the extra plastic was an issue.
Another good test is the 5mm step object,
When my e steps where off, the bottom would look good, but as it came up to the top 5mm cube it would squish and turn out all rounded.
Update - I replaced/upgraded the 40mm extruder fan on the Printrbot Jr. with a Noctua model and this problem has completely gone away.