£2K to spend on a new bike - any advice?

Faroon Posts: 9
edited June 2011 in Road buying advice
I have about £2K to spend on my new bike - I currently have an Aeron TR frameset with Campag Mirage groupset, on Khamsin wheels. It's fine as a commuter, and winter training bike, but I need something lighter to race on. I do Duathlons, Triathlons, but also longer sportives (I'm entered into Etape Cymru in October, for example).

I need something that'll be quick for the races, comfortable for the sportives, and has some upgrade potential for the future.

My current choices are:

Felt AR5 - great frame, but "only" 105 groupset, and fairly hefty wheels. Also over my budget, slightly.
Kuota Kebel - I can just sneak SRAM Rival/Force onto it, and some lighter wheels, but the frame isn't as good as the Felt.
Ridley Orion Limited Edition - it has Ultegra on it, but it's a more sportive frame than a racing frame. It is only £1800 though.

Do I go for the better frame on the Felt, and upgrade the wheels when I have the cash? Or go for the Kuota with the better groupset, but accept the less aero frame? And save a wee bit of cash.

I'm swithering. Any advice from more seasoned buyers?