My guess would be that the digital 49-way would make a better 4-way than an 8-way stick.
My reasoning here is that you could set the 49-way to read only the extreme positions on the stick, so a position of x=2/y=3 would yield the same UP signal that x=0 and x=1 do.
You would still be able to hit the diagonal, but only in the exact diagonal area x=3/y=3.
The problem that 8-ways have with playing 4-way games is that they trigger the diagonal too close to center.
You can play 4-ways with a worn out restrictor (worn to a circle like the 8-way) because the switches sit farther away from the actuator on the 4-way than they do on a properly adjusted 8-way.
Also, the actuator is smaller on the 4-way.
If you bend the leafswitches on an 8-way away from the actuator, it will perform better on 4-way games because it gets harder to trigger the diagonals.
If you bend the leafswitches AND replace the actuator, it becomes even harder to hit the diagonals.
That is why the Tron sticks are able to do the 4-way/8-way thing.
They have the diagonal restrictor that guides them away from the diagonals, but the leafswitches are close enough that they will allow 8-way in the sweet spot.