I vote VZ in 7.62x39 as well. I own a CZ858 and have also handled and fired extensively the T97, which is nice too. My CZ with factory folding stock in folded position is shorter than the T97, which is important to me for transporting in my pack. Having owned - past and present - many .223 rifles, I can honestly say that 7.62x39 is a superior caliber. It hits harder, is accurate, and cheap to shoot. The 858 is a proven design that works and works well (I have yet to have a failure of any kind in mine).
But most important to me is that the 7.62x39 is a great hunting/survival round. Hypothetically SHTF, then the larger 7.62x39 can easily take deer or larger game, protect your family from perpetrators and shoot through walls and cars much easier than the .223. That alone is why I’ll never sell my 858.
The T97 is a nice gun too, and surprised me by how compact it felt. It shoots well too! The two sh!tiest things about it though are the mag release and safety. Such fail in those two designs. And the cheek weld can be an issue, especially if you’re running an optic. You’ll get a chin-weld if you’re lucky.
