cant tell ya about the sidi, but the alpinestar t10 is pretty good. The soles on mine wore out a little quick though. Left sole lasted about 16 days of riding the right sole lasted alot longer, but it wore out too.
Don't forget about Gaerne SG10s. I believe most people would put them in the same category as the tech10s and crossfires. They are a very high quality boot. I know some pros wear them as well. Made in Italy.