3.0 is enough for up to about 350Mbit, but ISPs really want you to use 3.1 now, more efficient on their network. But if you can find a 3.0 one on their approved list and it saves a good amount of money, it should work. However you may have to replace it in a year or two so factor that in. Of course by then it may be time to upgrade to a 4.0 anyway so bridging the gap with a 3.0 for a couple years may make sense. Though if they upgrade your speed to much above what it is now you won't be able to take advantage of it during that time.
You can get a refurb of the 8200 off amazon for $75.