Yeah 10 mins sounds about right. It does vary depending how much WOT your giving it, and what engine is in there. (.28s will be less economical).
These things do rev high yes but shouldn't rev high at idle. As long as your clutch isn't enagaging its fine.
A little smoke is what you wnat to see. If its heavy blue smoke its too rich. light whitish smoke its fine.
You should shift into second whenever you have a fairly long straight and you give it everything. If you're reaching max revs and its not shifting you need to adjust the shift point screw.
Hope this is what you were after and have fun