White Labs WLP001 is great for high gravity beers, I have made several successful beers in the 10+% with this strain. Its clean and leaves little to no off tastes you might find with other strains. I would just recomend making a starter a few days ahead of time, don't waste your money on two packets!
Here is the profile off the web site:
WLP001 California Ale Yeast
This yeast is famous for its clean flavors, balance and ability to be used in almost any style ale. It accentuates the hop flavors and is extremely versatile.
Optimum Fermentation Temperature: 68-73°F
Alcohol Tolerance: High
Review this strain
Read other reviews for WLP001
Read FAQ for this yeast
Listen to audio from Chris White about WLP001
I agree with HP_Lovecraft; make a huge starter, aerate the wort extremely well, use yeast nutrient, and go with 001. Let that go until it stops (hopefully at the end of fermentation). If it stops early, pitch the big yeast to finish it off. I have done this successfully with Wyeast products, so it can't be that much different.