I keep going back and forth. Until my camera arrives it remains academic
The Tilta cage looks slicker and better fitting. I love the Tilta cable locks. Much, much better than anything I've seen anywhere else. Also really like the look of their screen hood. I am also intrigued by the V-Mount cage they have planned for the future that mounts under the camera cage.
However once you get away from the stuff custom made for the Pocket 4k the rest of the ecosystem is less attractive to me. The various plates and connectors Smallrig offers are clean and functional with lots of options while also being much more reasonably priced. Also a little less custom. Easier to adapt and grow down the road without being locked into one system.
The first of the Tilta reviews are starting to trickle out with deliveries. Hopefully there will be better info and comparisons soon.