If you are not considering astrophotography, dobs give the biggest bang for your buck.
I too started with a poor alt-az mount, ditching it for a photo tripod for my 2" refractor. I learnt an aweful lot with this set up in the nine or ten years before I got my C5, which then again, I mainly use in alt-az.
I digress. Mate, you will have no problem with a dob coming from a poor alt-az. It will actually proove itself a breeze.
Thanks for all the replies. I was hoping for such responses I can keep a large dob in the garage or tool shed then use a hand trolley to move it maybe 10 metres to an open spot in the driveway. Out here in the country there's no street lights and limited light pollution so with a large aperture and eventually some nice ep's i hope to get some solid enjoyment from it - and to introduce my kids to it too
I'm thinking about a GS or Skywatcher 12" dob or similar
I can keep a large dob in the garage or tool shed then use a hand trolley to move it maybe 10 metres to an open spot in the driveway. Out here in the country there's no street lights and limited light pollution so with a large aperture and eventually some nice ep's i hope to get some solid enjoyment from it - and to introduce my kids to it too 
