Don't overlook the Ironheart Vest...that's the easiest way to get your first Iron Heart maneuver. Once you have one of them, martial study is more useful. Here's a list of the Iron Heart Maneuvers, their type, and the prereqs.
Level 1
Punishing Stance (Stance, 0)
Steel Wind (Strike, 0)
Steely Strike (Strike, 0)
Level 2
Disarming Strike (Strike, 0)
Wall of Blades (Counter, 0)
Level 3
Absolute Steel Stance (Stance, 1)
Exorcism of Steel (Strike, 1)
Iron Heart Surge (Other, 1)
Level 4
Lightning Recovery (Counter, 2)
Mithral Tornado (Strike, 2)
Level 5
Dancing Blade Form (Stance, 2)
Dazing Strike (Strike, 2)
Iron Heart Focus (Counter, 2)
Level 6
Iron Heart Endurance (Boost, 2)
Manticore Parry (Counter, 2)
Level 7
Finishing Move (Strike, 3)
Scything Blade (Boost, 3)
Level 8
Adamantine Hurricane (Strike, 3)
Lightning Throw (Strike, 2)
Supreme Blade Parry (Stance, 3)
Level 9
Strike of Perfect Clarity (Strike, 4)
So after you have the vest you're open to all 3rd level maneuvers (and Iron Heat Surge is absolutely amazing). Take Martial Study once and presto, you can get anything up to 6th level, and even one eigth level maneuver. Take Martial Sudy once more and you can get any maneuver other than Strike of perfect clarity. The bottom line is that with one item and a few feats, you don't even need to multi-class or make the huge investments required by the Master of Nine.