Amlodipine is being marketed as Norvasc in North America. I am not too sure about the patent rights, but here in Canada we still pay through our ears for it. I pay $89.52 for it every month (this includes taxes).
Not everyone would be willing to tolerate its side effects. They can be much more unpleasant for some people than those of Diovan, notably: headache, peripheral edema AND cardiological adverse reactions. However, most of these are dose-dependent (as are the therapeutic effects), so lower doses might be OK. The average reduction in blood pressure with the once-daily dosing is about 12/6mmHg.
I find Norvasc has fewer cardiological side effects than my former CCB, Felodipine. The peripheral edema is about the same. A big pain in the....legs. :) :D