I view from Chrome on iOS and it's quite decent. The only issues I have tend to arise whenever I'm attempting to quote another user and want to omit part of the text or during other text-related editing/deleting. The iOS UI contains a few minor bugs when highlighting specific portions of text to copy/paste or delete. Often, it will highlight the entirety of the text instead of the portion you're trying to select, which can be a royal pain in the arse. This used to not be the case pre-iOS 9 (IIRC, that's when the issue started). Hopefully iOS 11 will finally address it.
As for how the site displays, it's pretty much just as clean as the desktop version. There are a few minor font discrepancies, but iOS does a good job getting around them with its formatting. In many ways, I actually tend to prefer the look and feel of the iOS rendering of the site over desktop.
A few years ago, I had a Galaxy S3, and I remember having quite a few issues with trying to get the site to display properly. It was cool being able to access Flash chat from my phone, as terrible as the interface was on such a small screen.