The 8" rim supports the sidewall much better now, so you don't suffer from the sidewall flex that the stock rims had on initial turn-in response. The lighter overall weight is even more impressive. There are no adverse scrub radius/bump steer/torque steer effects that i've noticed.
These tires are actually very good,.....but the weight of the car in combo with the stock width rims just doesn't have the responsive feel that I like.
With the exception of the tread pattern these tires have the same specs as the Bridgestone so-3 pole positions that i've had on my mk4 before. They aren't as quick to respond as the so-3's but the progression of slip/grip is far more stable/predictable.
So far, with my standard spirited driving, the tires have held up quite well with even wear all around,.......but i'm still only at under 4k.
As for clearances, 10mm is probably going to rub up front(while trail-braking through a dip), even with my sport springs/dampers. I wouldn't go more than 5mm up front without worrying.
In the rear 10mm with 225/45's will probably clear fine with a rolled lip.
A 37 or 38et might be a good compromise.
Optimally, I would go 40et(+5mm) with an 8" rim and 225/45's.
However, I will be upsizing my tires to at least 235's, and maybe 245's(depending on internal clearances), so I will fill out the pokeage a little there.
I will be autocrossing the car soon too, so i'll let you know what happens.