We do and I know Q does too.
I was amazed what a difference it makes and how quickly you can learn some really core balance techniques which really help with your overall control with bocking.
We're taking our slackline to Cliffhanger this weekend and we're set up next to MAverick slacklines who are probably the most active slacking group in the UK. To be honest I bought our slackline for our crew to play with while we're camping at festivals etc. A bit of fun for us when we're winding down in the evenings but I can see it being the total opposite and we're now looking at setting up our own slackline club.