When driving I usually use Waze, which doesn't have lane assist and prior to this I used to use a paid version of Tom Tom which did. Don't think it makes a huge difference to me either way.
Having just traveled through the Glasgow, Edinburgh, and London, I can say with confidence that I would have appreciated lane guidance greatly for the 7 million roundabouts I went through.
I didn't know google maps did this or I would have used it. I was using Waze instead, as it's my default.