Is it worth buying used bikes of old models? I am going to buy a road bike, and my budget is about 1300$.

And I'm faced dilemma: 
1) new 2015 (next year) road bike, for example Merida (aluminum frame, shimano 105, carbon fork)
2) used 2009-2010 road bike, for example Bianchi (carbon all, system fsa, ultegra 6600, mavic rims).

By photos it seems that the old bike is in a very good state (without scratches, etc), new supplies (chain, cassete, brake pads)

So, if we assume, that the state of bike is good indeed (attentive care, etc), then, is it worth buying 5-year bike? 
Technologies progress nowadays, so difference in 4-5 years is a huge gap, or it's OK?
In bicycles, the technological advance is not as fast as you might think. This is due to the UCI, which blocks a lot of new technologies or is slow to allow them in races. So I think as long as the older bike is in good shape, there won't be much difference. Maybe it's a nine-speed instead of the modern ten or eleven, but that doesn't really make a difference, especially not if you're not going to ride pro.

That said, be careful about carbon frames and parts. They might be damaged from falling over, crashing or similar, without the damage being obvious. Look for (deep) scratches in the paint job, hairline cracks (especially around joints), discoloration or deformation.