Our club routinely tows to 3000' AGL (field elevation 537') for student flights, and unfortunately also for most other flights - a lot of glider pilots wouldn't want to hear what I'm saying about them in the cockpit when I take them to a boomer at 2000' AGL and they hang on for dear life, finally releasing in sink at 3000'!

The more experienced pilots usually take a 2000' tow which is plenty, of course, without a ridge to use (rare in our part of Illinois)

I've taken high tows on occasions to do acro, but not when there is a crowd waiting to fly - usually a flat calm day anyway.

The trouble with using time for tows is that every tow pilot takes a different amount of time, either by the way he flies or how aggressively he works lift during the tow. I can usually get two full 3000' ft tows done in the time it takes a few of our "more conservative" tow pilots to complete one tow...

Kirk