This is basically just a mental exercise. It presupposes that a group will sit down not just with the intention of ruthlessly optimizing their own characters but to synchronize the builds to work together. And when you do that you can come up with ridiculous things. But it is no more ridiculous than pornomancer builds with unbeatable social skills, gunslinger adepts with high 20's dice pools to attack, Cyber-trolls with more than 40 dice to soak damage etc etc.
Also, if you think they are unbeatable, all it takes is one guy with astral perception to drop an ARO on the tac net and several others to start firing the grenade launchers. Sure, against opposition with no magical support they are hot death on a rocket, but cyber characters against low end opposition without high end combat skills are also hot death on a rocket. Basically you are saying "we would really kick ass against opposition that is bad at countering what we are good at." Any GM worth his dice bag will have you fighting bug spirit swarms, toxic shamans with a piles of bound spirits, draco forms, shedim masters, vampire cabals, etc.