I believe all those units are based off of the ELM327 chip which is manufactured by ELM Electronics. They will all communicate the same way. You can do a search for ELM327 on Google and probably come up with a nice list of various options you might consider.
From experience I know ScanTool.net to be an extremely reliable resource (might cost more but you will get it quickly), ProScan is a distributor of theirs. There are some ELM327 interfaces manufactured internationally that offer extreme discount and it may be worth your while purchasing elsewhere if you are in no hurry.