Wow - Markus!
You're really going above & beyond on this. Looks like the MRP-F300 may have an overheating problem, though.
Price wise it looks like the PDX 4.1 comes up on ebay once in a while, so it may be a better deal than list. But you mentioned the PDX-F4 - is it just a newer version of the 4.1?
Thanks again -
John