have the BG-7....
on my Sage 9140-4 greenie... Casting the 8/9/10 windcutter with tips and Airflo's Delta Long (65' head - mid-spey head length equivelant) on BG-7 spools, with 200+yds of 30lb dacron backing... no problem fitting either lines on there. if you're willing to spend the extra money, can't go wrong with the BG-8, and will certainly have plenty of room, but even the BG-7 will work for you.... note, the differences in taper, etc. may allow me to fit the Delta long in the 8/9, while i wouldn't be able to fit Rio's mid-spey in the 8/9, at least with the amount of backing... something to think about... still, I think if you can get 175 yds of backing on there, you should be fine, unless you're talking about BIG waters like the Thompson, etc....
The BG-7 balances the 9140 well to... and yes, i'm talking about the balance on the swing!!!

:chuckle: :chuckle:
feiger