I think 1:8 (when using a cascaded system) is enough for by far most conditions.
It also dependents on the way the sailmaker cut your mainsail. Redhead sail like alot of downhaul, while Goodall and Ashby sails like noticeably less. I don't in which camp Ullman sails fall (standard on Blade F16)
1:8 does leave alot less excess line on your trampoline which is a plus.
The only time I really enjoyed my 1:12 was in the very light winds of two weeks ago. Here I could really downhaul my mainsail, allowing it to become flat with only very little mainsheet tension. This low mainsheet tension in turn allowed me to sail with a significant amount of twist. But you can achieve this with a 1:8 system as well; just hunk on the mainsheet and then pull on the downhaul to the correct setting and release the mainsheet again. This will lead to the same effect.
I've thought about downgrading to 1:8 as the cascades systems develop luff tension so well, but as my 1:12 system is now fully sorted and operating without any hitches I think I'll stick to that. I solved the excess line problem in a very satisfactory way as well.
You'll be fine with 1:8 and besides it is very easy to upgrade the Blade F16 system to 1:12. Just fit one single block to the boom and a 3rd single block to the sail and run the second stage line through these blocks eee presto ! a 1:12 system. See the drawings in the other post.
Wouter
Wouter, do you think an 8:1 DH on the Blades superwing mast is enough, especially to allow you to easily adjust DH from the trap while singlehanding? To me it sounds kinda light on the leverage. Doesn't everyone else use 12:1?