Anyone ever play with an IOtech Serial488/4?

Hi, All, I have this IOtech Serial488/4 IEEE-488 quad serial box here, found the manual easily enough, but haven't yet set it up. Does anyone on the list have any experience with one of these? If so, I'd love to hear about any lessons learned or "gotchas". For those that haven't seen one, it's rack-mount box with a 68B09, some ROM and SRAM, a pair of Z8530s, and a TMS9914 GPIB chip. It gives you four buffered serial lines on your IEEE-488 bus. They are still sold new, for new prices, and used for about 10% of that. It looks rather straight-forward to talk to, but I thought I'd ask in case there is some "notorious" feature of them. Given that I'm heavily loaded with PETs and not with HP equipment, I'll probably go that route. Thanks for any tales, -ethan