I like it for modelling with. It is the first solid modelling cad I played around with, and has evolved from basic beginnings to a fairly comprehensive modeller.
Its strength lies basically in modelling parts to be machined or cut, rather than entire assemblies. Nonetheless, I model assemblies in it anyways See some of the attached fingernail shots of stuff I have modelled. I don't, as a rule model for the fun of it, I need that $$ incentive , and all of those parts or assemblies I have machined or constructed.
It does not have automated dimensioning or multi-view 2d drawing output at the click of a button like Solidworks.
Even when the customer sends you a finished file, you might be surprised at the amount of CAD work you might do to the file, to place the part properly, find dimensions and depths, etc.
Its good for all that, too.
While I don't hear of that many users who throw away their previous cad programs when they get OneCNC (their time spent learning another cad is valuable), there are some of us diehards who use only OneCNC. Version XR2 is so much better than earlier versions to model in. It is very fast actually, once you learn the gui and the modelling tools.
I think the type of work your customers ask you to do determines how fancy your cad program needs to be. Also, your position in your own shop, if you have to produce prints to use on the shop floor, you'd probably want something more automated for that purpose, like Solidworks.