Not much.The clubhead is extremely large in appearance. Even though clubs max out at 460cc, this seems larger, especially from front to back.So if you like a clubhead that looks larger than even the biggest models, you'd like this. The deep front to back dimension is meant to increase MOI (resistance to twisting) on off center hits.
The shaft, for one.I was surprised, as the www.Aldila.com website says that their R flex shaft is for 90-100 mph, which is my swing speed range. It says that the S flex shaft is for 100-110 mph, which is faster than I normally swing.Don't you believe it, unless Callaway has trimmed the shafts differently so that they play softer, or re-labelled them somehow. I found both flex shafts to feel whippy, with the R flex feeling exceptionally whippy. The R flex felt like an A flex, and even the S flex felt too whippy to me, and I rarely play a stiff flex shaft unless it is a soft Stiff in most other brands.Perhaps it was the combination of the soft feeling shafts and the deep front to back dimensions of the head, but I found that I had a very high trajectory with this club.It never felt good hitting the ball, due to the weak shafts (even the S flex), and I even had some trouble with the ball drawing way too much (duck hooks) with the R flex, as perhaps the face was closing due to the soft shafts.It wasn't like I was having a bad day, as I hit other branded clubs well that same day. I normally swing in the 90-100 mph range, with a fairly even tempo, so this shouldn't have been happening according to Aldila's shaft charts on their website.
Can't recommend this club unless you want a club that plays much weaker than normal, to satisfy your ego.You can say that you play a Stiff flex shaft, when really it feels like an R flex shaft, but your playing partners won't know.And you'll get added height to your shots if needed.This club may be suited to some golfers, but not to me. I think slow swingers may actually like this club quite a bit, and they can get it in a flex stronger than they normally play to assuage thier ego.Aldila's swing speed recommendations seem to be way off, unless as I said, Callaway marked the shafts differently so that they are actually softer than labelled.I'm not a nitpicker, as I've played other Callaway branded clubs and liked them.A few years ago, they had a driver known as the Hyper X 460 Ti driver, and I liked that one very much.And I even liked the Callaway FT-iZ hybrid that I tried the same day, but this driver seems like an 'old man' club.I seriously doubt that Phil Mickelson has this stock shaft in his version of the driver, if in fact he plays this model.