It really depends on what you like to cook and how well you do.
Tim and I use spares - trimmed St. Louis style. More meat and, in our opinion, better presentation - FBA doesn't use garnish so the larger ribs fill the box better - i.e. no lettuce to hide the mistakes! :D
I know Phil prefers loin backs.
Southern Brethren BBQ Competition Team
"It's all about getting paid!" - Myron Mixon
"I love being hated in my hometown!" - David Hair
KingFisher Gator Rotisserie cooker, WSM, Stainless 5 burner with IR gas grill, Turkey Fryer, Weber JD Commemorative grill, slightly used Bandera chamber for future use as a cold smoker, Masterbuilt 40" insulated ELECTRIC smoker