I think you can rotate it in any orientation to get it to work for you. The starter cover should be square which means it can be in any position that best clears your header.
Actually... I think I just realized what you were asking. Does the spinstart shaft itself need to be reversed. I would guess that it does as the losi one doesn't have a gear changing it's direction. It's direct drive to the starter shaft. The HPI/offset type starter has a gear that turns a second gear that the starter shaft of the engine is keyed to, which means the spinstart will spin the opposite direction of the engine.
Also, looking at the photo's of the starter, not only can you rotate it 90 degrees at a time, the outer housing is keyed to the starter input housing with raised notches so you can fine tune where you really want the starter input to be. That's a pretty cool design.
However, personally, I'd go with the pull-start version. Makes break-in more annoying, but feeling the tension on the pull-start helps tell you whether or not the engine is hydrolocked whereas a roto starter can just damage stuff. Also, a PS means less junk to carry on your person.
