More than enough. Check out Scott Bennett's excellent write up:
http://www.endlessweather.com/2010/12/27/choosing-a-datacardtether-for-chasing/
Scott - I did find that mine was set to "home only". I'll have to see if this helps on the next chase. I'm not sure if it has always been on that setting or not. I plan to try that Tether program, but I'll wait until right before a chase and do the 7 day trial before I buy it. Unfortunately it doesn't appear to be on sale for $25 at the moment.