[Ronbo]

40x optical zoom with any kind of decent low light preformance means a huge lens. (optical glass hasn't improved much over the years, or ever will)

Your pretty limited with these requirements: either JVC or Sony pro series ($$$) are about all that will manage this. Not to mention these are rather large camcorders.

For the few times you'll actually need that much zoom I'd just go with a telephoto adapter. This would mainly be outdoor stuff, so the light loss won't be a big factor. Not to mention at those zoom levels you pretty much have to use a tripod.

One thing I should mention, I hate not having a viewfinder for outdoor use. A lot of the newer camcorders don't have them and that panel is tough to use in daylight.

Sorry, I know this makes the choices that much tougher...