A 730 mah nimh battery is a smidge over 2 oz.

As skypilot one stated, you don't need heavy 6-7 oz H9 rails... but rather at best, 3 oz standoffs.

So split the difference... 3.25 lbs.

But I disagree about tank size... It hink most would put a 20 oz tank with a 1.60 and get about 12 minutes... You could put in a 12 oz tank with the BME and get more than that... so take off weight in fuel is a half lb. more in glow fuel...

Really theu are prett6y much neck and neck. Then add to that the hoop jumping a lot of guys end up going through to get a consistent 1.60... pumps, regulators, add a little weight...

Cost? In a seasons flights you'd get all your money back in fuel savings.

Lastly... see how much a used 1.60fx s worth and see what a used DA50, or BME 50, etc is worth...

Lots of benefits with gas... even if it was only not having to de-slime your plane every evening...