I played on dialup for a year or so before I got broadband. I also had to use dialup my freshmen year at WCU due to packet filtering. It uses DirectX 8 netcode so even with a low ping you have to lead-shoot but theres very little difference in leading and shot registry between a 50ms ping and a 600ms ping due to the size of the object you’re shooting at.
On dialup you’ll get around 300-450ms to most servers which is fine for most multiplayer engagements. Only trouble you’ll have is hitting the fast, little mechs at long range but if you stay with the group you usually don’t have any problems with getting picked off by little buggers.