Marketpress HTML5 Theme ?

More of theme question but in support of Marketpress

I need to convince a client to go with WordPress – Marketpress instead of custom development of a proprietary ecommerce system (yes, people still are convinced that is better)

is there a Mobile HTML5 theme that would work for Marketpress?

It looks like SimpleMarket might be a good choice but are there others?

Need to have both a desktop shop and a mobile device shop that really looks good on an iphone.

Unfortunately I have not set up Marketpress yet, so not really sure what to look for. While I hesitate to bring up other premium theme suppliers on this forum, if anyone knows a theme (heh heh) or other framework that would be great.