I've been very impressed by the design, fit, and finish.
My only disappointment is the loss of the MTO program. It was something that I was looking forward to trying one of these days.
I'd choose the one that fits best. On me, for instance, the McGregors don't fit well whereas the MacNeils are perfect. If both fit well, then get a McGregor if you want a leather insole or a MacNeil if you want a Poron insole. Also, the McGregors come in a couple of colors -- burnished brown and oxblood -- which are not offered for the MacNeils. The MacNeils are available in a brown grain leather for a more casual look, which is not offered for the McGregors.
I had a similar experience to about 8 pairs or so then ran into a bad stretch were 4 had to go back due to huge lumps in the footbed(all that vibram gumlite sole) then got back on a good streak.