Has anyone had to make a decision between two kinds of chemo? How did you choose?

I agree with a second opinion but you should be given written information on all proposed therapies to read and consider. That should be standard even if you are not being asked to choose. You also need to ask what dangerous effects means for you  - do you have any pre-existing condition that would make a difference? It is almost impossible to tell beforehand what side effects you might get from any chemotherapy, or how serious they may be but there are some more likely with one therapy than another. Best wishes.