to answer ur question nice and simple. yes, hella is a hell of a brand
their one of the best. philips, hella are used in OEM HID kits.
i think they are better than mcculloch, but mc... is also a great brand. just buy whichever is cheaper and better for u. both are real easy to install and both are gonna do the job well.
as for mounting the ballasts, i have mounted them right behind the headlight. i have hella and so far so good.