I have used 1shopping cart for years now. I complain about the same thing....it is too slow. The search engine is not easy. You have to put the customer's name in exactly or it does not find it. Recently, I stumbled upon a new cart. Premium Web Cart. I used the trial version and was happy with what I saw. I am now on the advanced package and very glad I switched. The searching is 110% better. The report search options are much easier to use.
The customer support person was extremely helpful. If you are using something else...switch immediately!