Completely agree with you. I've been trying to find another set of 16's but they're either ridiculously pricey or the other end of the country.
The comps are just my road tyres for travelling to and from events. Once I'm on track the semi slicks and TD's come out.

Engine is holding up very well (touch wood). It's done 134k miles (the last 4K on track). It doesn't have an easy life at all.
It uses virtually no oil on track and doesn't smoke at all. It's got Millers nanodrive 5w40 in it at the moment. That will be getting changed after Cadwell in November.

I plan on stripping the engine down over winter and refreshing some parts. Maybe I'll stick a set of cams in whilst I'm there