We test Lefty's driver

	Callaway FT-i driver (10-degree, neutral bias)
Contact: www.callawaygolf.com Technology: Inertial design pushes discretionary weight to corners of clubhead, raising MOI (Moment of Inertia) resist clubhead twisting on miss-hits. The 460cc head features Titanium face for increased ball speed, distance and forgiveness with Fujikura Speeder graphite shaft. Light, regular and stiff shaft options with 9, 10, 11 and 13 lofts and draw or neutral faces. Price: £349

Square-head top view I can immediately understand Phill Mickelson's thinking when he admits he'll be carrying two very different Callaway drivers in his defence of the US Masters green jacket this week. He wants the new FT-5 - with its more traditional pear-shaped design - because it allows him to shape shots on certain holes like the 13th and 14th where he needs a soft draw. But he's also carrying the square-headed FT-i. "With this club, I'm not really trying to manoeuvre it or curve it, I'm just trying to hit high bombs,” says Lefty. And after my first introduction to this much-talked-about weapon, I can see how it appeals to the Masters champion. For over 30 years, I've been more of a 'steerer' than a 'clouter' when it comes to driving the golf ball from the tee. I like to put my ball in play, not spend time hacking in the rough, so I tend to opt for the low runner and then rely on my short game to make a score. It's not pretty but it's effective. Yesterday, however, my expectations in the midweek medal were low after a couple of weeks inactivity, when I joined a group of mid-handicap schoolboys on half term, all of similar standard but relishing the idea of giving the golf ball a whack.

Distinctive sole of the FT-i driver Almost old enough to be their grandad, I expected to be outdriven big time off the tee but was pleasantly surprised how the Callaway FT-i kept me on the short stuff and earned me their respect. Its head is more compact than I'd anticipated after using its similarly-styled Integra iDrive clone successfully for a few weeks, which is a slightly flattened version with an elongated rather than square face. The FT-i is a little deeper. As my confident grew, following an arrow straight opening drive, I was able, with more freedom, to extend the backswing and finish with a high follow through. Callaway, like their Nike rivals and other less well known makers of similar drivers, claim the square head shape has allowed them to increase the MOI (Moment of Inertia) and the amount the clubhead automatically twists at impact to produce a straighter hitting driver. But does a square head really make a difference or is it merely marketing hype?

Not quite as shallow-faced as some of its rivals I've done some research and discovered that when the MOI increased from 2,000 - 4,000 gm cm2 there was a significant improvement in performance on mis-hits. However, from 4,000 - 6,000 gm cm2 the difference is apparently insignificant. Most of the bigger 400cc to 460 cc drivers have about 3,500 - 4,000 gm cm2 MOI, and perform very well. One report stated: "The latest square drivers have improved the MOI to 5,300 gm cm2 but the improvement hardly compares to the improvement from 2,000 to 4,000 gm cm2. A case of diminishing returns. The reason manufacturers are doing this is to impress and be different and also to approach the MOI limit placed by the USGA and R&A. Any time there is a limit (on cc or MOI) golfers assume that being just under it is good but we doubt they will see any measurable difference unless you really miss the sweet spot. Expect to see a return to 400cc drivers and traditional shapes but currently square is cool." Sounds a bit sniffy from the techno-boffins but personally, the square deal suits my game and all the square-headed drivers I've tried including the Nike SasQuatch Sumo2, the Turbo Power XQ MUTO 460Ti and the Integra iDrive have appreciably increased my confidence factor standing over the ball at address. Results have been similar but based on yesterday's performance the Callaway FT-i edges it, with a more compact head and a 44-inch Fujikura Speeder 586 shaft that's just under an inch longer than most standard driver shafts. Almost at will I was able to deliver a penetrating flight - even with a 'neutral bias 10-degree head as opposed to the draw/closed option, the square head tends to accentuate a slightly toed-in look - with slight miss-hits tending to send the ball on a gentle fade. I was also impressed with the distinctive orange black and silver headcover with an easily accessible magnetised flap. The Golfmagic Verdict Rating: 9/10 Summary: Whether, as one rival manufacturer suggests, the square-head fad will last more than three months is open to debate but judging by feedback we're getting on the forum, golfers faced with nipped in fairways to counteract modern technology in terms of distance, seem to enjoy the confidence that these revolutionary heads give them. In the meantime Mickelson is doing his best to keep them in the public eye at least in the high profile majors. *We want to know about the clubs in your bag - as well as the balls, shoes, waterproofs you use. Submit a user review for the chance to win prizes every month. And if you've got equipment to buy or sell second hand you can do that too, in our popular classified section.