no, i think the .30 weighs about the same as the 25 LA with muffler.

i am not sure about the prop because i only have tried the 9-6 and it was terrible for hovering. maybe a 10-4? 9-4?

i used a 2 ounce fuel tank. i fit a 4 ounce one in there, but took it out for weight reasons and also with the 2 ounce, i get 15 minute flights.