For the guys that have switched from 6R30 to 8R30 how much more productivity do you feel you actually have gotten from the size jump. Currently run 2 6R30 and I'm considering going to 2 8R30s but a little concerned about maybe "overkill" with the two 8 rows. It takes about 10 days to harvest my crop now. I don't feel comfortable about going down to 1 lifter, and I don't want a 6 & 8.