and how well ventilated the printer is.

Elmoret, can you explain better how ventilation affects the exturder temp. Is cause a non enclosed printer will have drafts and cool the extruder more than an enclosed one?

OK, to clarify, the E3D thermistor and stock thermistor are largely the same accuracy, in the order of a couple of deg C.

The difference is that the stock thermistor is mounted onto the extruder nozzle, while the E3D (as per most other hot-ends) thermistor is mounted on the heat block. In normal operation, the heat block can be 10-15 degrees hotter than the nozzle surface: so one is not 'better' than the other, they're just measuring different things!!

People get confused and say the solidoodle thermistor is "bad" or "inaccurate" or "measures 15C too low" because it's different from the majority of other hotends. It's actually a bit of an argument to work out which is more an accurate reflection of the true molten plastic temperature in the nozzle. In the end it doesn't matter - this process will work in a good +/- 10C range anyway, so all you need to do is pick a number that works and run with it (even if that number doesn't really mean anything itself). Maybe the plastic is actually leaving the nozzle and hitting the print at 200C? Who knows? EDIT: elmoret probably does!!

In answer to your question: I've settled into running ABS through my E3D v5 at 230C and it seems to go well - I haven't seen much improvement in warping or interlayer adhesion varying between about 225 and 240, but really can't comment as the test was highly unscientific.