I will state up front, I have not used either of these lathes.
That said, my first lathe was the Delta equivelant to the 1236. I had it mounted on a bench because I could not afford the stand. This works out well until I tried to turn an out of round log. It was a harrowing experience to say the least! Much of it has to do with the instability of the bench and the lathes ways being of a less than substantial cast iron. That said, I turned many beautiful (to me anyway) items on it and that particular project definately pushed the limits of the lathe. If I were do it all over, I would have probably added several 4x4s to the stand and hundreds of pounds of sand or shot to help absorb the vibration.
I would start out by looking at what you can afford (and add to it if you can), figure that over time, the price of the lathe is less than half of what you will spend on tools, chucks, grinders, etc. It is just the largest single purchase of the hobby.
There is more to consider than sheer mass and size capabilities. Look at the thickness of the bed, the heft of the banjo and tailstock among others. Talk to members int eh local clubs to see if they have any pros/cons about their lathes. Just because you can turn a 12" item, does not mean you can throw any 12" piece on the lathe. Invariably, if you buy a lathe with 12" capacity (which is stated over the bed, not over the banjo) the piece you want to turn is 13" or is 12" until it warps.
This may seem as a bunch of disconnected (hopefully not) ramblings, but it is early in the morning and the coffee kicked in.
