Dob, 8", 10", 14"...
Goto or push-pull...
SCT vs dob...
While all good arguments for each, do you know what these look like, their size, storage/set up/ tramsport requirements, and most of all - what can your wife deal with physically if she is the one using it by herself any given night?
A 14" dob is a heck of a big and heavy beast.
REALLY heavy. While it may sound really sweet to have such aperture, their are some serious things to consider about such an instrument.
With so many suggestions and options available to you for the sort of budget you have, I would suggest you first go go an astro club meet and see exactly what all these different scopes both look like, but start coming to understand what is required to transport, store, set up & take down, potential dew issues for both scope and mount... You will then make a better informed decision that will better meet your TOTAL set of requirements, not just the thrill of a new scope and potentially end up with a poor choice.
If you are in Sydney, there are many clubs, and each with their own urban and/or dark sites, ranging from Waterfall to Mona Vale, Belanglo State Forest to Katoomba Airfield, Linden Obs and Mt Bowen across the Blue Mountains. And at any of these meets, you will find most helpful and knowledgeable people.
You may dind that an 8" SCT with a single arm goto mount might best suit you and your wife, or an 8" or 10" or 12" or even a 14" dob. But without actually knowing what you are getting, and only armed with
talk, it does not make for a really well informed choice. And your wife should be a part of the decision - the surprise is already there when you say "honey, let's get a scope!" Now if you make the surprise part of a visit to an astro club meet, there's an added element
Burning $2000 outright does not mean you are getting the best scope for the two of you.
Alex.