For forward compatibility, I'd go for a multi-card reader like this one:
Kingston 15-in-1 USB card reader (unfortunately sold out right now at Buy.com Canada...
Or one of these:
ATP 15-in-one Card ReaderI have a very nifty EdgeTech 3 port USB hub/multi-card reader, but I can't find a Canadian outlet selling it. However, I've found it on eBay, but ending in 22 minutes...
http://cgi.ebay.ca/USB-CARD-READER-BUILT-I...1QQcmdZViewItemActually - no rush...the guy has stacks of 'em - just search on "USB CARD READER + BUILT IN 3 PORT HUB FOR LAPTOP PC MAC" - and he ships to Canada, and they're Buy-It-Now items and so cheap I'm considering getting another one for on the road!! Note: it is a POWERED USB hub - so it does have a small power brick, about 2"X1.5"X1"
Further edit re: Zio card reader - there are MANY, many complaints online about this reader not working past 10.2, Neil - and causing kernel panics after sleep etc. Interesting that your experience has been so different. Is it the exact same model?