I was banned for using lowerping.com which is a tunnel service.

It was a 72 hour ban and it was quite a hassle to get any warnings etc removed. It's quite possible that I could continue to use it now and never get banned again but with Blizzard's customer service its pretty risky.

My ban expired long before I got any response from wowaccountadmin and they will not discuss any ban issues over the phone.

The -100ms ping was great but still not sure it's worth the risk especially with multiple accounts involved.