I would much prefer that my credit card is charged in U.S. dollars. A recent purchase at $320. U.S. Cost me $7.00 more when E-Bay "helped" me by converting the cost to CDN. Dollars.
Second, before buying a new product from an E-Bay seller, make certain that the manufacturer will honour the warranty.
These two concerns will probably have me steer clear of E-Bay for future purchases.