I too have the '07 Langster. I put some Deep V's on there... I've got mixed feelings on them. Going with Mavic the next time around. If you want to try some Deep V's/Formula hub build, I got my set from Wheelandsprocket.com for around $300. And this is purely my opinion, but get Machine side-walled rims. I've had both on my back wheel, the machined sidewall seems to hold up better. I'm not sure if they reinforce them better or not, but my last one folded over on itself and couldn't seat a tire. Another side effect is weight.

Here's a link:

http://wheelandsprocket.com/itemdetails.cfm?ID=7129

Pink, yellow, and white are in stock for them with machined sidewalls.