If you make your floors look like a project on Trading Spaces, people will notice. You cannot achieve a hardwood floor appearance with plywood. Never. A good sheet of 3/4" hardwood plywood is going to cost about $65 (assuming you don't plan to use fir plywood). That is over $2.00 per square foot. Unfinished oak strip flooring is the same price if you are willing to accept minor defects and do the finishing. You can buy pre-finished hardwood flooring as low as $3.00 from Lumber Liquidators or similar wholesalers. Do the math. You don't save much by pretending, and the results are not even close.