Hello Graeme,
The weight of the Europa is less than a Series 1 or more or less equal. I don't have my Series 1-4 string anymore, but remember my aching back. However, the doubleneck was murder. It weighed over 18 pounds but felt like 50!. I made a custom wide leather strap that went from my neck out to my shoulder to distribute the weight, but it only helped a little. My left arm would start to fall asleep after about 20 minutes, then I would have to sit down, which of course would put my leg to sleep too! It was a real looker, but only for a quick number or two. Great in the studio as well.
There's another thread for it here at the club. The John Judge model, 4 string fretless on top, 8 string octave on the bottom. Series 2 body with Series 1/2 custome electronics. Zebrawood top, Dragon inlay, 2 necks of red LEDs. Really bizarre!
You can see it at the G-Guitars web site. They have it for sale at $9,995.00 USD. Well worth it at today's prices. When I got a Modulus Quantum 5 string, I added Alembic electronics and finally got a break for my back. That's when I let my old Alembics go.