The boat is a lot more sensitive than other classes, so if you don't respond quick enough to the wind changes then the boat will slow quicker. That said, it also accelerates quicker if you get it right.
I find upwind that the kicker is the most important control, if you are hiking, pull the main in and you'll soon see how much kicker you need to pull on (at least take up the slack). Once thats on you should then be able to point. If you are stalling then get some downhaul on, leave some belly in the foot of the sail for some driving power.
I'm on the shelf with the keeping the boat completely flat, this is one of the few boats that i've found a small bit of leeward heel is fast, for me anyway. It also allows you to hike harder if its heeled slightly, as your bum isn't in the water slowing you down.
The 7 rig I find great until you let the kicker off and you are sitting in, this stops you pointing straight away. So i've tended to leave kicker on longer than i would in any other class and pull downhaul on to compensate for hooked leach, rather than letting the kicker off. Not sure how everyone else works with that?
If i'm hiking then i can generally out point most things on the water, Solos and OKs this weekend.
Upwind speed at around 5 knots is fine as far as i can tell from my GPS.