Peter gives good advice Laurie, and he is right about the QHY8, from memory, its a similar same size sensor as my Canon 1000D DSLR chip and therefore gives a comparable FOV.
Using the CCD calc, your Stellarvue 80ED will definitely fit more of the Lagoon in the shot, as shown by the two attached pics from the CCD Calc.
Your better bet would therefore be the 314L as you can see in the pics.
The first shot is with the 314E and the second shows what the 314L would show in the FOV.
Maybe the extra dosh is worth your while....
Cheers
Chris