This year our team used treads for the first time. We were very pleased with their results. We got them from a company in the UK so there was a long lead time, but it was well worth the wait. They are specifically designed for climbing obstacles. They also were made from Kevlar, making them very strong. There is little to no wear on them after a year of use.
Here is the company website if anyone is interested.
http://www.thistle.uk.com/