i believe the weak synchros are actually 5th, 6th and 2nd normally
Weak in what way? That they expolde & need rebuild or that they are slow to engage when pushing it on & really just annoying but liveable?
from personal experience, annoying but liveable at first, it makes changing gear difficult as you need close matching shaft speeds not to crunch, untill they give up and its almost impossible to change gear without crunching.
There are many perfect boxes out there though