I like Deuvilles, they are 'soft' in their power delivery, but they are comfy, quick enough and easy to live with. I guess it all comes down to what you use the bike for... I'd hate to scratch on one, but If I had to ride a bike long distances or for commuting then I'd choose one straight away.
A lot of people also say that the Diversion 600 is a 'flat' bike and not very exciting. I'd have to say that this may be true if you compare the bike with some of its direct rivals (Hornet, etc.) but my brother and I were quite impressed with the one he bought recently. It pulled a large sidecar at 70mph and returned 50mpg, I can't see that as being poor for a 600cc bike. We also rode it solo and it was very nice.
It's subjective this biking lark eh?

Cheers
GC