You can trust Mike Mc (I think that is the Earthshine guy if I recall correctly) . He is not allowed to call what he sells a true Arduino because the Earthshine guys either MAKE them or resell the freeduino type clones. It is a requirement of the original Arduino Team that "clones" NOT be called Arduino... since ONLY the true ARDUINO approved boards are made by (or with the approval of) the ARDUINO team.
For all practical purposes, they are identical in everything but the name.
So... like I said... you can trust them and you should have no problems.