I've used the Pronto/TV-76 combination for years as a good airline portable scope, but have opted for a C5 as a travel companion more recently for reasons of light grasp. In giving up some FOV, I gained alot for objects like M57, M13, M81/M82, M31 and a host of other deep sky gems that 3" just can't give me a big enough taste of. I would say the only object I really miss a good 3" refractor for are really wide objects such as the North American Nebula with a filter. I've pondered just about every other options to gain some aperature without going much over the 6-8 lbs for an OTA range. I found the C6 to be just a little more than my Mircostar and Bogen can handle without the shakes. Would love to check out what anyone's ideal airline scope might be.
Starmaster 11" f/4.3 ELT
Celestron C8
Televue Pronto