Highly likely your '06 had been derestricted. Pretty easy to do and a very high proportion of owners of pre '14 models (when the factory started derestricting them) would have done it.
edit: 2010 models had a claimed higher power figure which was not actually evident on the ground. The enormous goofy foot cans on the Roadsters added a lot of weight which most likely ate up any extra oomph. 2014 was when they were derestricted in the first three gears, not 2010.