The 135i is definitly more nimble. I had an E90 330i before my 135i. To be honest I liked the handling of the E90 better. Felt more planted/stable/less roll. Both are fun but definitly different.
2009 135i: AW/CR Aluminum Trim, 6 speed, M-Sport, Premium, Heated Seats, Ipod, BMW Performance Pedals, BMW Performance SSK, BMW Performance Exhaust, BMW Performance Grills E93 M3 FSB