Chris I haven't got a stock bike – I bought the frames and built both bikes myself. The Alpine only weighs a tad more than the 5.
IMO its all down to what sort of riding you're going to be doing. If its general XC and trail centres I'd get the 5. If you're after regular trips to the Alps, uplift days and more aggressive use I'd consider the Alpine.
Having said that, I took my 5 to the Alps in 2007, gave it a really good pasting and it coped admirably, embarassing some much bigger bikes in the process, and I wasn't hanging about 😛
Sometimes when I ride my 5 I wonder what the point was of me building the Alpine. It seems to jump better than the Alpine, but the Alpine does land pretty sweet with that extra bit of travel.
I honestly think if I did an enduro event on both bikes there would be nothing between them.
The Alpine does look pretty sweet though, even with rental forks 😛
Here's what it should look like;