No, I haven't tried it yet but I'm thinking of trying it. It depends on how my first Woodforde's Wherry turns out. If I get decent results from the Wherry then I'll try the Headcracker next. My only issue with the Wherry was it didn't drop as low as I'd have liked it to; OG of 1.041 now down to 1.014 (which I understand is average for a Wherry, though it won't be the 4.5% advertised on the front of the tin).
Either way, my pre-bottling sample tasted lovely and complex so I imagine the lightly carbonated finished product will be excellent. If it is, I'll try the Headcracker next. If you do make that kit, please post and let us all know how it turns out for you!