Help With Enhancement?

My current girlfriend's ex had a rather large (supposedly it was 8 1/2 inches). We haven't had yet & I am afraid that I won't equal her expectations (I am 7 inches on my BEST day). I have read some reviews of enhancement pills, but you can never trust those because they could be forged. Does anybody have any recommendations of which pills that I should get (I am considering Vimax because they are natural & rather cheap *$31.66 for a year's supply* but I am not sure)?