I've only ever written in Advanced on RPG. This is more to do with the fact that the plots and groups attract me more in that section. The best roleplays that suit me reside in Advanced. That's just how it has been when I've looked for a new roleplay. 

I guess a lot of it depends on how you like to write. I love writing detail. I like to imagine and play out a scene in my head and that means that I *think* I probably write a lot of description, exposition, introspection. I like to know how a scene feels; that might come from the sights, smells, sounds. I also tend to write Elder Scrolls/High Fantasy where that level of description is the standard, imo. I like to be immersed, both when I'm writing and when I'm reading other character posts in the group.

Quantity is not always the way, I agree - and some of my posts are shorter than others, whereas some are *very* long but I like to make sure that everything makes sense, nothing is a waste. Part of that comes from editing - reading the post back later and maybe trimming out a sentence or two here, a paragraph there - making a more cohesive piece of writing. 

That said, I follow the standard set by the roleplay - if the posts are shorter, I'll probably keep to that level too. If they're long winded and very personal, then I'll write like that.