Bio 500T have very different balance from Bio 400T. But it still swings easy on the court. So far i prefer 400T, but next week i will try 500T with full poly and i'm really intereseted how it will perform.
Btw i'm thinking about getting 200 Lite too, I like the specs and it's very cheap in my country right now.
POG 100 - SP Firestorm (1.25) 49/46 lbs, Bio 400 Tour - Yonex PTP (1.20) 51/49 lbs