Should I get a bike that's too small for me? I'm considering buying the 2010 model of the Pinarello FP2. They're substantially cheaper than this years model (~£700). However, they only have the 55cm frames in stock.

I'm 6ft tall, looking at this size chart it says the 55cm frame is suitable for people up to 5ft 9in. 

Would it be advisable for me to get a bike of this size?

Is it going to cause me problems? Is it not such an issue? After all it's a massive saving but if the bikes unrideable (for whatever reason) then it's not worth it.
Riding a bike in the wrong size (either too small or too large) for long periods can lead to all kinds of lower back, upper back, neck and shoulder issues en various leg injuries, mostly in the knee. Also, your power output can be reduced significantly. So a properly sized bicycle is important.

However, "properly sized" really depends on the rider. Sheldon Brown has a lot of good info, but mostly it comes down to:


Try the bicycle to find out how it feels.
Compare it to your current bicycle.


Finally, you can compensate some sizing issues in this specific case with a longer stem and/or higher saddle. How this works also depends on the relative length of your legs and your upper body.