I am the general manager of a large hotel chain and my housekeepers use these Ready Clean microfiber cleaning cloths.  These are the only way to get your glass and mirrors streak free!  We have these on all the housekeeping carts!  These are affordable and you can wash them in the washing machine over and over again as they do not require any special washing.  These microfiber cleaning cloths are heavy duty and do not fall apart as we have used them hundreds of times! Highly recommended!