With Mac's Spaces, I can switch to another screen running Windows with Control-Rightarrow (using a non-Mac keyboard here). It's really seemless and I've never found a single drawback to it.
If you're fine with your company's data possibly being compromised in the future then continue your ordering from Lenovo.
I will still buy from them because I always make it a habit to do a clean install whenever I get a new computer just because of all the crap every vendor adds to consumer PCs.
However I could be wrong, and perhaps there are companies that feel betrayed. Custom images may be a thing only large companies do.
As a consumer, I still view Lenovo as the best PC hardware and would buy again but would probably be suspicious of any new purchase (as in, wipe the HD and install a store-bought copy of Windows myself). That said, I use the Thinkpad line which was unaffected by Superfish from what I know.