thomas31,
We have been using Vi Technology 3k3 and 5k machines for about 5 years and have been very happy with them. They are easy to program, mechanically robust and have good support if you need it. If possible, you should narrow it down to about 3 companies and try to set up a demo with each them using your own product. All of the suppliers listed have decent reputations, but a hands-on demonstration is the best way to determine which is right for your application.
(http://www.smtnet.com/Forums/Index.cfm?CFApp=1&Message_ID=66286)