In reply to Weekend Punter:
I also have a PX Pro Carbon (large, SRAM Rival 10sp groupset).
I bought this bike in June 2014 to replace an alloy bike (Specialized Secteur).
The first bike to be delivered turned out to have a cracked frame - likely due to a combination of poor packing, followed by bad handling during transit (Handlebars had been rotated and were in contact with the top tube at the point where cracked).
Emailed PX with photos and the bike was collected/replaced without further question.
The second bike was fine, apart from the wheels - these were poorly put together, 2mm out of lateral true and even had slack spokes. Couldn't be arsed to return to PX again, so paid LBS to true and tension the wheels. In the meantime, I used the bike with my 'best' wheels (Ksyrium Elite).
As a 53 year old punter, this bike is great and more than able to cope with my ability. Being in hilly Cornwall the 50/34 compact and 11-32 SRAM WiFli gearing is perfect for me.
It is pretty light, yet still robust (so far!). I ride it on the stock wheels with 25mm tyres in winter and the Ksyriums and 23mm in summer.
For £799 (plus £24 to get the wheels sorted) I think Planet X represents good value for money. BUT, - don't expect the type of service you get from LBS.
P.S. I'm now considering getting a Ti 29er from PX to replace my aging MTB.
N