Diff. between MBL 1611 E and F?

see a couple of "E" models for sale - does anyone know the dif.between the E and F and can the E be upgraded to the F?? also is it worth the upgrade?? thanks, K
Yes you can upgrade from D to F. I have not done the upgrade yet though. It is listed on page 2 under accessories on MBL-USA web site it retails for $3000.00 I am curious as well to know if it is a worthwhile upgrade. please let me know if you find out anymore details.