I've 'done' O-16.5 ( Wheal Tiny, a 2 level pasty mine with working hoist), so was considering going the full hog and a Class 08 and a couple of wagons. But I came to my senses.
I am an O Gauge devotee now after returning to the hobby after 45 years. I honestly don't regret it and would recommend it to all. These 08's with sound are great....