It is here: http://www.zzstove.com/sierra.html

I have a the one pictured and also an older model, I do not have the windscreen and have never had the need for one, even on the lake Michigan shoreline where it is always windy.

As for grilling, they make an accessory :http://www.zzstove.com/ws_g.html

Never tried it, I have grilled with mine two different ways. I once did a steak by sticking a couple pieces of coat hanger through some holes in the pot supports after getting some coal built up, didn't work well. Also have used it with a folding backpacker grill over the stove.

This one:http://www.campingsurvival.com/stursteelfol.html

Again ran the stove to produce coals then grilled, also a so so result it's not really big enough to build up a decent amount of coals. Now i have done hot dogs etc on a stick over the stove a couple times also, that worked better. I like the stove and it is decently stable with a one liter pot or a little bigger. We used a larger pot on a group trip and drove 4 large tent pegs in around the stove on the ground to support the pot and that worked very well.

As for boil time i don't remember the numbers but in college my room mate and I did this test. 2 first generation Zip stoves VS a MSR whisperlite and a coleman peakone stove. Both of them running white gas. Zip stoves were using firestarter sticks and pine cones. Challenge was to boil 2 1/2 cups of water. Wood stoves beat the gas stoves by a decent margin.

Ok now the downside, they black your pots. Lots of folks have tricks for this, soap the outside of the pot first etc. My trick is to wash the pot well afterwards (gets a lot of it off) and wrap it in a bandanna. Basically I think the downside is not that bad compared to buying and hauling fuel.

Any more questions let me know, this is one of those "best gear i ever bought" things for me.