If you simply want to prioritise traffic, say for example voip traffic above http traffic, is it a good idea to set low limit-at on both, then higher priority say priority 1 on voip traffic and lower priority say priority 2 on http traffic so that the priority kicks in immediately and always favours the voip traffic?
After posting this I found some more examples in this forum which indicate this is the case. In fact the examples show no limit-at. It makes sense, the less limit-at, the sooner the priority kicks in.