best e-comm for full range computer store

we want to deploy an ecomm site, we have already installed OSComm, but have
found it lacking in essential feature we need. Basically, we need to be able
to take a XML data feed over roughly 180,000 SKU's or thereabouts and keep
real time pricing up to date. This will likely come from Tech Data, Ingram
Micro, etc. We are not interested in channelonline's solution

We have also looked miva and have even talked to some custom
developers...none of which seems like a quick, easy and cost effective
solution. Our thinking is there has to be some package out there we are
missing. The number or computer reseller sites out there is huge. Obviously,
we feel we can do it better and bring products to market cheaper and faster
than our competition

any and all ideas or help appreciated. especially useful would be anyone
with any experience in utilizing data from above sources.