It really does look fab!

A couple of questions spring to mind while I mull this one over:
Will the HeadSix perform well with rechargeables? I have a couple of Maha 9.6v and I think they're slightly longer than regular alkalines, so I'm wondering if they'll even fit to begin with.
Is "low-current" essentially the same as "low-gain"? I'm wondering whether the HeadSix might struggle to drive my 40 Ohm PROlines or 30 Ohm Edition 9s.
Thanks in advance!