John, just about every first scope buyer will say yes when asked if they are interested in astrophotography. The other commonly asked question is: what do you want to look at. And the virtually ubiquitous answer is "everything" perhaps with the occasional preference for planets.
SC, they are all different telescopes, each with its strengths and weaknesses.
- ED80 gives you the widest field of view and is great for cruising the Milky way and the Magellenic clouds. With just 80mm aperture, it runs out of light quickly at high powers.
- 150mm Mak will give you the highest magnification and show you the fainter objects but has a narrow true field of view.
- ED100 is somewhere in between, and is probably the best general purpose scope out of the three. It will show you extended objects like larger clusters and nebulae, and still have enough aperture to show qiute a bit of detail on Saturn and Jupiter.
I notice you are looking at the GOTO HEQ5 packages with these scopes. Most of the purchase price there (over 2/3) goes into the mount and the GOto computer. And even that mount is only just good enough for astrophotography.
Unless you have photography first and foremost in mind, I would not bother getting a scope (and mount) for that purpose now. Just get something for visual astronomy first. The cost of the telescope is usually not much of an issue when it comes to astrophotography. It's the mount that dominates the cost of a setup.
With a Dobsonian nearly all your money goes into the telescope, so you are getting a lot more aperture per dollar, which means you will see a lot more at the eyepiece: more stars, more nebulae, more galaxies and more detail on planets and deep sky objects. The Dob mount is simple, inexpensive, but very effective for visual astronomy and for a large telescope it is a lot sturdier than EQ mounts costing over $1000.
If you get an 8 or 10" Dobsonian, you can always buy an EQ mount to put the tube on later on for astrophotography.
PS. I'm not a big fan of motorised Goto mounts. I find them too restrictive. ArgoNavis push-to is nice though, but so are star charts IMO.