You don't need the High Drive model. The "drive" refers to the dead key imput. You are planning on putting a low dead key into it so you only need a Low Drive model.
Good luck !
Well since the only difference between the 350 and the 350hdv is the fact the 350hdv has a variable potentiometer so your previous post lends no technical value to this thread and subsequently detracts from it.
The link Quicksilver posted clearly shows this. Texas Star Export Feature Chart