A browser is like any vice. You don't want to make any changes once you have gotten use to something. Firefox can be irritating because they have added unintuitive features from time to time but so far I've been able to figure things out.
I would avoid anything by Google because I have enough of the big brother experience from the PAP:(
I use Safari but infrequently because of familiarity with Firefox. Speed is not important because my Macs/PCs are using i7 processors When Mozilla introduces Firefox for the iPad I will definitely try it out. If the interface is similar to the PC I will use it.