Standing is not a problem in lower gwladys. The problem is you need to stand and duck to see anything because of the roof at the back. Sitting down, you'll be fine but often vs Arse/Chelsea, etc the lower Gwladys turns into a terrace, so you need to stand. On the back row of lower gwladys you need to kind of dip down and angle you neck whilst standing to see up the other end so people often just stand in the isles.