Well, that’s the correct preposition in English. It would also be the more logical preposition, therefore you probably can use it in Esperanto.
There might be two problems with my comment above:
(1) the online Oxford dictionaries says that "compared to" is OK. (2) I'm not sure that you can use "kun" for this meaning of "with".
Ekzemple, li ofte diris "mi estas tre pli bona al vi".