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Glen - you've asked this question before on the forum - so I fear you are going to get the same answers. Without knowing how good your eyes are , what your collimation standards are , how you prepare the scope for viewing , and whether you use high power in a skilled way Its hard to answer. With a well mounted optic , that is properly cooled and collimated on a night of reasonable seeing the focus will have a fair amount of snap even up to a 1mm pupil .
A mirror of 1/2 wave or more PV wavfront error will not show this behaviour. With high expansion glass as used in the GSO's , there may be thermal issues as well. As I pointed out in the recent 16" GSO thread - I've measured three 16" mirrors that were around the advertised 1/12 wave RMS surface which is around 2/3 wave P/V wavfront error - Strehl would have been around 0.5 or less and definitely no contrasty snap at any power. These mirrors would not be showing you fine detail on the planets, but for a 16" aperture scope complete they are good value if you are after value.
Are you happy with your images in view of the money you invested ? If so then I'd suggest you have good value.
The experience of observing is certainly not all about the largest aperture . My favorite views at the last IIS camp were through a 12.5" Conical primary F6 and there were a number of larger scopes there up to 24" . With a 13mm Ethos there was sufficient steadiness, snap and contrast to give the image a `reality' that belied that fact we were looking through an atmosphere ( a fact I could not forget looking through the larger scopes ! )
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