The numbers are the number of teeth in each front chainwheel. I don't know why Bianchi lists them in the opposite order.
To find which one is better, you would also have to know the tooth count for the rear sprockets, and compare each of the combinations. What most people look for is combos that give uniform spacing and minimize duplication of ratios while also minimizing how many times you have to shift from one front chainwheel to another. Many bikes have three "ranges" with some overlap for each of the front combinationss, so you can leave the front deraileur set to the center chainwheel and just shift the rear deraileur except for climbing or downhills where you need the extra power or speed.
There have been whole books written on this subject. Some people have been known to disassemble cassettes to change individual cogs and change chainwheels, all in search of the "perfect" setup.