The LO is the most compact model with a low and forward CG location that promotes a low-mid trajectory. It’s the most iron-like design of the group and is most likely to work for those with faster clubhead speeds.
I ended up putting him in extra-stiff shafts steel in his 5-iron through wedges and graphite in his woods. I traded his bladelike 4-iron for a Ping G400 hybrid and replaced his one-piece forged irons with TaylorMade P790s both of which produced superior performance: 10 yards of extra carry with his new graphite-shafted hybrid and nearly 14 extra total yards with his new stiffer-shafted irons.” — Andres Victoriano True Spec certified fitter
A forged carbon steel clubhead further enhances feel at impact while an internal face perimeter cut-out design increases the effective hitting area on the face by about 15%. This provides more forgiveness on off center hits and better ballspeed retention overall.