Hi,
I guess it all depends on what you need it for, but i have both an Axminster 12" disc sander and a Clarke combined belt/disc sander. The latter is a recent buy but a great disappointment. It was their 8" disc version, not the smaller cheaper one.
The Axminster disc sander is quiet and pleasant to use and I have it on a wheeled base so it goes where I need it. It also has an Earlex vacuum cleaner in the base that is hooked into it and both can be switched on together.
In contrast the Clarke machine is noisy, vibrates around and needs a wedge under one leg as the base casting is far from straight. In truth, I really should return it. I left an honest review for their web site that never got published!
For curved work I have a number of Carroll sanding drums of various sizes and a fixture for my pillar drill. Not as good or convenient as a bobbin sander as you tend to just wear one bit of the paper but again they are quiet and very well made.
The one I wouldn't be without is the 12" disc sander. I can't recommend it enough.
Regards,
Colin