Make mine a JMI NGT-18 please.
So it's not up to modern AP. Neither is a Dob or an old GEM Newt (although the older GEM Newts can be relatively easily upgraded for it). Otherwise, you have the portability of the Dob with the Eq mount.
Dobs certainly aren't for me. I used an Alt-Az through my teens (not including the 12.5" Observatory Cave that I used, but was not mine) and developed a hatred for Alt-Az. I used a 12.5" Dob at the Sky Bar in Tucson almost 2 years ago. Trudy had to wash my mouth out with soap after.
Now get off my lawn....
I think you'll find the JMI NGT-18 does not have the portability of a Dob. This review says it weighs about 250 lbs and is best setup with two people.
If one wants tracking in a large, portable Newtonian, either an equatorial platform of a ServoCat seems to be the popular solution.
This thread is about Parks. Whether or not one embraces the Dobsonian, it is the most popular and most effective mounting for a larger Newtonian. If one wants a portable and truly large aperture scope, or even just a truly large aperture scope for visual use, a Dob is about the only option. Anything else would be so unique as to be of interest due to the fact that it wasn't a Dob.
Maybe Parks and Scope City would still be a going concern had they moved forward with the times.. But they didn't.
Enough about Dobs, this the classics forum..
Jon, I know we have very different views of Dobs. So be it. BTW, the early Dobs ARE classics, and the discussion segued to what killed a particular type of classic, so I'd say the discussion is germane.
That said, I agree with you. The Dob revolution brought us very large amateur instruments. But as others have said, below a certain size, make mine Eq thank you. And we can disagree about the NGT-18. I'll still take that over a Dob, thanks. Considering a horseshoe like the NGT would not be that hard to make, and given so many Dobs balance so low, I'm surprised more ATMs haven't copied the NGT. As I said, I learned to hate the Alt-Az mount. Some are OK with it. Not me.
I also agree with you that if Parks had embraced the Dob revolution, they might still be here. From your description of the 'tude at Scope City, I doubt going to Dobs could have saved them.