I have both Turn A and Xi (yeah just to keep the thread rolling. Discussing S ranks right?)
Turn A is indeed terrible for most people and I can't blame them. It does poorly on almost everything like the melee in mode 1 is terrible. W3 has some dash-like properties and can be used as free ZBS, but don't count on it too much. It has a beam magnum-like weapon that USED TO pierce infighter, now its just a regular beam rifle.
What I did with Turn A is that:
1. Get scale up, switch to mode 2. Swing dat hammer for maximum lulz and rage from enemy units. Tag along a team mate, scale up, hammer anything that tries to melee your team mate.
2. Make it a substitute spec bomber. Back in 4th Gen, it was funny to add C3 SP and SP Awakening parts. Turn A has good SP stat in mode 1. Make use of it. Anything around 70% HP will die from it.
This doesn't make Turn A good, but at least it is creative. When I play with my friends, they always ***** about those cheap tactics.
爆ぜろリアル！ 弾けろシナプス！ BANISHMENT THIS WORLD!
00 Raiser, 00 7S/G, V2AB, Infinite Justice, HWS v, Master Fuunsaiki, God Fuunsaiki, SR Sazabi, Crossbone X1 Kai, X2 Kai, Harute (Final Mission Type) Stargazer, Crossbone X3, Sazabi
Upcoming projects: Arios Ascalon (100% Complete!), Crossbone X1 Skullheart (100% Complete!)
Playing Phantasy Star Online 2
IGN - ホモゲーバスター