Go for it!
I did sort of the same thing, making TV-ads (lots of product modelling and animating) for a couple of months. Though I had a feeling from the beginning I would not stay very long (not enough designing involved), it was an awesome experience. I learned a lot of useful modelling and presentation skills, worked on a 3d ad incorporating live and cgi footage, and made some good money while keeping my eyes peeled for a better fit job-wise.
Like Yo said, you’ve already shown enthusiasm for the job. Don’t let this be a chance you’ll regret not taking later.