I am The infusion takes 1 hour then you stay for 1 more hour to make sure you don't have a rough side effect (I haven't heard of any in the hour after but some need Benadryl while being infused). Pretty sure the troubles you've been reading about were those trying to get tested for the jcv, which you've already accomplished. The side effect of pml is almost not existent for the first 2 years.
I am not trying to talk you into Tysabri, just wanted to clarify some of your info
Linda