I bought tier 4 and added two sites, which should let me index 2500 pages per site a day. After one day it only did 173 pages on one and 151 pages on the other. This is after all 25 worker accounts are active per site. In saying this, I will update the review if the speed picks up. As of now, I don’t know how Tier 5 is any better then Tier 1.