Might pick up a Yamaha MX or Roland DS / tiring of iOS

The other day I played my old and inexpensive Yamaha YP-235. I was shocked how good it sounds. Now that I am using a mixer > stereo PA for my home studio, everytime I play that gear, it sounds and feels better than my iPad, which has a ton of musician apps, including Korg Module Pro and Moog Model D.

So now I’m thinking of picking up a relatively inexpensive ROMplr synth, like the Yamaha MX – which is based on the Motif library. Or a Roland DS.

I want to have something besides the OP1 around to give me other sounds that I can play in my home studio. And pipe into the OP1 for some tracks or samples.

The nice thing is that I can pick up a used Yamaha MX for under $400.

Anyone have any experience with this gear?