Well, I sold mine a few weeks ago now. To tell the truth it didn't make that much difference on the big dob, and you have to remember that although you are worried about swapping out the MPCC between EP's you still have to tune the Paracorr for each one... Also as mentioned there's that FL increase - which I think is a bit naughty in this instance as a barlow will also reduce coma to a certain extent for much less on the pennies front
Oh - and you can't use some barlows with the Paracorr
Arthur