>Or do you disagree with a progressive code?
Depends very much on the country, but in many cases yes. I believe that it can create a situation that disincentives paying taxes altogether.
In my case instead of paying almost 50% tax rate I've moved all of my income into a friendlier legal climate where I only have to pay a tenth of that (something a lot of people can do for only a few grand).
Although it's also worth noting that I've got ethical issues with financially supporting the Finnish government, and those have played no small part in my decision. I'll gladly expand on that if you want.