I don't know who your watching, but 10 minutes minimum is the general rule at my fields. I personally like 15 minutes with a touch of extra fuel "just in case".

I am currently getting into the electric arena, and the costs are very high. In order to get similar performance to the 40-46 glow with flights of 10-15 minutes you pretty much have to go to LIPO. In the 40-46 size range that means adding an expensive charger that can handle more cells than a parkflyer uses.

Lets take a look at some basic, very rough, ballpark numbers. Let's assume that the electric motors and speed control cost the same as the glow engine (which they don't). Let's say you want to fly for about an hour after work one day. With glow, that is around 40oz +/- depending on particular engine. Thats about a third of a gallon or around $7.00 in fuel. Now, if you want to fly for the same hour with your Lipo powered electric you will need 4 packs, probably in the 5s4p-6s4p range. What will that run, about $200 each? So, that is around $800 for an hour, vs $7 for the hour.

In order to break even on those admittedely very rough numbers, would take around 114 hours @ 4 flights per hour. Granted, the glow fuel is gone, but 114 hours is a lot for most modelers. Thats two hours per week, every week.

There could be an advantage there depending on how many years the lipos can last. The flip side to that is when you wreck the Lipo powered plane it is very possible that you can destroy the pack...and are out the $200 (ballpark from above), while with the glow you are out one fuel tanks worth. Thats just the loss in battery costs, not to mention the possible motor loss, because we assumed engine/motor costs were equal.

I think there may be other advantages such as no mess etc to the electric, but cost is somewhat high comparatively.