If you don't need more than 133 Watts, go for the dual battery boxer. The DNA200 is simply far ahead of the 350J in terms of feature set. Makes no sense not to get it if it is an option. Also temp control is more accurate and doesn't use PWM. The reason the accuracy is so good is once you have a proper TCR curve, its nearly dead on. The 350J now supports something similar, but only if the curve is linear (thus less accurate for instance when you breach 450+ degrees with titanium).