Gimbal vs unipivot tonearms

The devil's in the details.

Ginmal arms or arms with two axis bearings if done correctly are superior.
They are also more expensive to manufacture. Unipivot arms are easy and inexpensive to make They are a little more difficult to handle as they wobble when you pick them up. They are more difficult to keep in adjustment and are more finicky to set up. They tend to have more bloated less detailed bass. The two exceptions to this are the Graham arm which is stabilized by opposing magnets and the Basis arms which are really not unipivots they are bipivot arms. There is a secondary bearing that fixes the torsional axis.
Tonearm wobbling and torsional instability are very bad issues in a tonearm as they can adversely affect the cartridges performance. 
I will never own another unipivot arm.  There are so many excellent arms available with wonderful bearing designs at reasonable prices. But, you can always make a unipivot cheaper if that is what you are after.

Dont forget the Well-Tempered Labs tonearm. I believe it is a quasi unipivot with much more control and little to no wobble. And yes, it has terrific sonics. Imo.