Hi Glen,
I am with Jose on this one. I wanted to purchase Ketron X1, but didn't care too much for the 61 Key or the action on it. Luckily, I own a Roland A70 so I recently purchased Ketron X4 module. I couldn't be more happy. Ofcourse, as others pointed out, the placement of the two intstruments is vital. I have a two tier stand and both machines sit perfectly on it.
Now I have a 76 key great action of Roland along with exceptional sounds and programming of X4. To me, it's a match made in heavens.