I bought a TDF about a month ago for my work/winter bike. On our bathroom scales it came in at 12kg (26lb in old money) it was mid sized one 54. I assembled it my self with no problems, it took longer to get the wrapping off than put it together.
I wanted to transfer some bits from my old work bike to this one because I liked the saddle on the old bike. I took the seat post out and it felt heavy, it has steel fitting on the top so I swapped it for the old aluminium one on my old work bike - saved 4 oz, my old saddle was about 2 oz lighter too.
I rode it for a bit and it did not feel right ( I had my old spd's on with the same shoes), I measured the distance between the cranks and it was further. If you lay the cranks down they are curved so the pedals are further out than usual. 1cm on each side.
I think this is to clear the chain as the block spacing is larger than on my old bike.
So I swapped the cranks and chain wheels back to the old 52/42 setup of my old machine and now its fine but its very close on the higher gear and I have had one lock-up when the crank it the chain, it pulls the derailleur forward. But the old chain ring was steel and the old Shimano 600 one was 8oz lighter.
The 36 spoke wheels are softer than the wheels I race on so soak up a lot of effort put in. The paint work was very good for a cheap bike.
Everything just worked when asseembled. I wasn't expecting it to be so easy.
Its a big jump between this and my racing kit, but there is a big jump in the price too. I think this is good value for money and I have had no problems with it. If you want to race, 600 quid takes you in to a much better bike, but for work or days out this is fine, I'm doing around 150 miles a week on mine without any problems.