Good idea to design free sites to look similar to sponsor?

[Alphawolf]

Does it make sense to design free sites (color scheme and fonts) to be fairly similar to the sponsor you are promoting?

I don't mean steal the sponsor design of course, just provide as many visual clues to make the transition from free site to sponsor page as seemless as possible so that the surfer feels comfortable.

Of course, one could go a shade lighter/darker and use different font sizes so it's not the same repetitive template.

It seems if a free site looks totally different in every way from the sponsor site that it would sorta make me think: "That's not what the sales picth made me expect at all."

Would 'sponsor themed' free sites tend to have better convertions?