Unipivot vs. Gimbal

What differences can I expect with using either of these?

I am using a Nottingham Interspace with a Rega arm and a Lyra Dorian. I am looking to upgrade the arm and could use some advice. My current system includes a 30 watt tube integrated, Revel M20’s, and a Lehman Black Cube. As far as price I would like to keep it under $1000 but I am not in a hurry. Nottingham uses unipivots but I want to know what the differences are. Musical concerns would include all genres.
My last two arms have both been unipivots [Nottingham AceSpace & Schroder Mdl One},before that I had two linear trackers {Walker/Air Tangent}.Both offer their own virtues,but for musicality VS detail retrieval,I am enjoying the unipivots.For an upgrade you might try the current production Ace Space arm.It makes for a great combo with the table.
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Both approaches have their attributes. But on your Nott table, you will likely find no better match than a Nott arm. A used Spacearm will be in your price range, but I highly recommend the Ace-Space if you can up your budget. I have tried many other arms on my Spacedeck, and none have bettered the Nottingham tonearms.

One thing not much discussed is the ease with which a cartridge can be destroyed with an unipivot arm. Any arm not secured that can come off easily is dangerous; will you never make a mistake? Can you afford to destroy an expensive cartridge? I dumped my unipivot in favour of a SME 312 and have never looked back. The SME performs very well, is a snap to set up, and has wonderful construction/finish.