not a clue. Looking at the specs the kossel has larger build volume.
Ah okay - still uses belt and pulleys, but instead of wheeled carriages, the carriages have cylindrical bearings and guide rods.
So more complicated. And dependant on how good the bearings are. Given that they could pick up dirt and crud over time - something a wheel is less likely to do - I'd still go for the wheel I think.

Given that Alexa has printed everything I've thrown at her, with precision and speed - I can't see there being any improvement. Just a different and easier system to build I guess.

If you can get the anycubic for the same price as the he3d - then just for the build size I'd go for it. The rest of the design and build looks practically identical to the he3d. Though it does come with a print area cooling fan - so that's one thing you wouldn't have to make yourself.
All the mods I've made for the he3d would still work for the kossel.