Mark is not only a knowledgeable and professional tech, he is an excellent businessman interested in service to his customers. He backed up an original paid for clean up when my desktop did not perform properly after his work on it. He took the computer back and determined that the hard drive was weak and the cause of the after clean up problems I was having with it. He took the computer back, installed a new and state of the art hard drive and made a new computer out of my three year old Gateway. No charge for the follow up and hard drive installation. Outstanding job and outstanding service. I will use Mark again in the future and refer him to anyone else who is looking for a really reliable source of computer repair. Jim in Tempe