In portrait mode it's kind of in the way of operation of engine controls because it interferes with arm movement. In reality I use it in landscape mode. I've got it positioned so it doesn't block visibility to flight or engine instruments and does not interfere with the stick or manipulation of throttle/prop/mixture levers. It does partially block visibility to the engine levers and heater/brake lock levers, but that's no big deal - I operate by feel anyway, with my hand/arm below the iPad. Manipulating the heater/brake lock, AP buttons, VM1000 buttons and transponder it's also more convenient to reach underneath the iPad. In this centered position my wife can also use it, though she has to use her left hand and getting to the Aspen dials/buttons is a bit more troublesome for her.
Note this is a Pro 11. A mini is half the size, of course and would be less intrusive. We use the 11 because the screen targets are all larger than a mini and my wife vetoed the use of a mini. If a mini were used there would be more leeway in positioning. I'm waiting for the RAM mini 6 EZ Rollr cradle to come out and will experiment a bit with it, just because that's what I do.
In this location it never overheats, BTW, as the sun can not get a good shot at it.