Let me chip in on the T4, I drove one as a daily driver for almost 3 years.
Current issues:
Gearbox issue a pain, however my mechanic is busy fixing that, which he says he can at a reasonable cost.
It is rusting, will need it fixed, once I am sure that gearbox is OK. Rust around windscreen a major worry on mine, they do not have good paintjobs.
With aircon in, it tends to die, when aircon cuts in. I would think it has some idling issues, but they are not getting worse. My mechanic can’t fix it, and just cleans it out, if I get annoyed enough, it goes to VW, so they can sort it out.
Past issues:
It was NT$150k all up and that included buying it and getting it into shape.
Computer on it crapped out, so did starter engine, the latter recently.
A local made Cefiro might cost NT$4,000-8,000 to take to the garage. The T4 will easily be twice that.
You need a good mechanic, which can find you second hand spares, if not it will cost you a fortune, repairs would run at least NT$50k-60k per year when used daily.
It drives well for what it is and feels rock solid.
It is not much fun to drive in Taipei or any other place where underground parking is a concern. I managed to find parking for it every time, it goes into basements with 2 meter of headroom, of which there are some.
If I get issues sorted with it, I plan to keep it as a weekend car/camping car/transporting bike car for as many years as I can. Basically, he devil you know, and I am fairly convinced that it has no other issues than the ones mentioned above. Also, getting another T4 would get me an unknown, so I stick with what I got for a long time.
I have a Cefiro too, and even though it’s very old, has been waterlogged, and has almost 300,000km on it, it is in daily use more reliable and a damn sight cheaper to run.