Not sure if there are any audio differences, and I suspect there are few people that own both who could comment anyway.
That said both are supposed to be good. Jez Riley French has recommended the MicBooster Clippys, but going by the date on the blog post, it might be before the Uši’s were available.
The most recent version of the Uši’s come with a detachable cable, so you can have both the 3.5mm PiP version and the XLR version just by buying the extra cable. Bizarrely it’s cheaper to buy an Uši and add the ‘pro’ cable than the other way round (I did this before Christmas, purely because the 3.5mm Uši was the only one in stock).
On the other hand, you can buy a Clippy and get it now, rather than waiting till Spring.