this may be a dunb question, but after you use the data transfer, does your user name and plus membership transfer also?
Yes, youre PSN ID (Username) isn't tied to one particualar PS3 nor is the PS Plus Subscription which is tied to the purchasing account, once you have transferred your data over simply log in with the same PSN ID & password you do now & your Plus Subscription will be there.
Make sure you deactivate the old PS3 & reactivate the new one though.
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