Update: this is turning into a bit of an epic!!
I ordered a SmartJoy Plus from www.darkplanets.co.uk
what can I say - ignore this company like the plague. Showed as in stock when I ordered it or I wouldn't have bothered. When that part of the order didn't turn up but was marked as "to follow" i checked the site again to make sure it was in stock and they'd removed all existence of it. Uh oh! After a week of phone calls they finally admitted that they wouldn't be able to get it and I cancelled my order for a refund. I'm still waiting for the refund.
SO, i got to www.consolesandgadgets.com
and ordered one since they're a bit more expensive but they showed as "in stock usually ships next day" after 4 days it showed up. Hoorah! Ah, maybe not. They obviously couldn't get it either and chose to just send one that works with Windows instead grrrrr....
It's a "Super Jox Box 3 Pro". Well, okay, it works in OSX but it ain't no joy box
There's a discernable lag between moving the stick and the keypress registering in Mame OSX. And obviously with the drivers being Winblows only there's no rumble support if i choose to use the proper PS2 pad. Oh, and try as i might i can't get the driver floppy to fit in any of the orifices of my iMac - LOL
I'm about to phone them up and give them a piece of my mind!
My conclusion is that the SmartJoy plus must simply be no longer available and using a decent arcade stick on the Mac is going to be a case of X Arcade or nothing at all