Upgrade Loadrunner 9.5 to 11.0

Hi all,

i need upgrade to my loadrunner 9.52 to loadrunner 11.0. can you please suggest me what is risks? what is the benefits?

one more thing

such as the impacts, schedule (To upgrade controller and almost 10 load generators, how long it will take etc....)

please inform as soon as posible

Thanks,

Chandra.