ORIGINAL: gade600sdi
The static thrust on the G20 is way less than the DLE20, but not sure what the absolute number. I own both of them and the DLE20 is much stronger and lower weight. Zenoah is probably better long term engine, though.
As far as fuel, 8-10 ounce tank is adequate for either, any more is overkill for a 15 minute flight.
What numbers do you have? I fly the G20, and it's an impressive engine. My DLE 20 is still in the box, so I have not yet compared them.