Those are versatile machines, to be sure. I have both the Delta press and the Ryobi. There actually significant differences between them beyond just the speeds. The Ryobi's motor, curiously, has no tag so I'm not sure of its HP. The Delta is 1/4 hp. They may be the same.
The Ryobi is physical larger and has nice nice features, like a geared crank to adjust the table height. The handles on the arbor (?... the part with the chuck that goes down) are longer and beefier.
As Jon observed, the Delta won't slow down as far as the Ryobi but they are fairly close in the top end.
Neither one of them probably belong in a professional shop. They're probably aimed at the hobbyist like me.
The Ryobi is probably meant for the hobbyist with a few more $$ 😉
My Delta was purchased new by me about 25 years ago and has never let me down. Jerry even used it for some work on my 261. My Ryobi was a gift from Paul Morgan and was his dad's. I have it set up as my mortising machine with a mortiser sent to me by Mark Smith.
That mortiser illuminated another difference between the two machines.... originally, I was going to use it on the delta. But... it was about .25 inch too big in its diameter and wouldn't clamp to the arbor. Sooooo.... Jerry made me an aluminum collar which was going to work elegantly.... until I discovered that the Delta arbor lacked sufficient travel to make it fit or work. It the table all the way Don and the arbor all the way up... the mortising bit still extended through the hole in the table. No Bueno, as the Swedes say...
So I tried the Ryobi.... after a bit of trial and error, I discovered Jerry's collar works great on the Ryobi if I inverted it. The Ryobi has plenty of travel and I have used the mortiser a lot.
Jon... interesting. I'll have to pay attention to the wobble now.
