Complete Online Store Business Web Site

I need a web site that would let me know perform the entire online business. The best would be a Zencart, I think. Must have standart pages, online store (complete and working) without any bugs, user friendly back end. I do not know what is the best right now on the market, so please provide enough information to review it. You will install it and make working on my server. I will provide all text, logo and images, as well as few products to test the online store functionalities. I do not want any bugs and I do not have a time to test it. I will use it for 2 weeks before I release a payment. If I find a bug or missing patch/file/mode/etc related to the program I will be very unhappy. Please respect my time. Therefore, only experienced people please bid on it.