I'm not aware of any handle variations on the 710 Axis unless they are done after-market, like Mr. Recupero's work. Like nearly every Benchmade, your choices are black, bead-blasted G-10 or... black, bead-blasted G-10.
Some common handle materials I use are steel, titanium, G-10, carbon fiber, linen micarta, aluminum, and dymondwood. For a given thickness, I believe steel is still the standard of strength by which all are judged, but for a given weight, I think all of the others except Dymondwood are stronger (the best strength/weight being CF, I think). Except the Dymondwood, I think 3/32" scales of any of these materials is strong enough to form the scales on a full-sized (3.5"-4") folder without the support of metal liners, but liners never hurt, either. Some natural woods are stronger than Dymondwood, but most are substantially less so.
I'm being very unscientific and discussing strength as my impression of the force required to bend or snap the material, but I think that will suffice for this topic. There are many ways to resist deformation, though - for example, G-10 is very hard to bend but cuts easily and thus cannot hold threads well. Steel may (at some hardnesses) be bent easily, while Dymondwood chips under similar stress.
In short, there are many handle materials available that weigh much less than steel for a given thickness and are suitably strong for folder scales, so I think it is a matter of looks, grip, and personal preference.
For grip, G-10 is typically bead-blasted to give a rough finish that feels great and looks awful. Micarta is typically sanded to a high polish, making it very attactive and somewhat slippery. Micarta can be bead-blasted but aquires an unattractive, powdery surfcae, and G-10 can be polished but doesn't look half as nice as Micarta (the two are very similar, but G-10 uses a glass-fiber weave whereas Micarta uses cloth or paper). Titanium, steel, and aluminum may be bead-blasted for a rougher finish, but this invites corrosion (for steel) and is not terribly durable. They are just as often given a satin or even mirror polish, where scratches are visible but also easily removed. The rougher the finish, the better the grip, but bare metal is always fairly slippery unless it is checkered or grooved somehow. Dymondwood and CF are usually given a very slippery but attractive high polish; some folks bead-blast both, but I have no experience with this.
Finally, one of the most-ignored areas of grip is the contouring of the handle. Even a highly polished handle can have a great grip if it is properly contoured to fit the curves of the hand. The trouble is that this is labor-intensive and requires the knife to be thicker as well, so virtually all production folders have flat handle scales with no contouring whatsoever. This is one of the biggest reason I enjoy replacing the scales on production folders. My AFCK, for example, has Micarta scales that swell smoothly to 3/4" thick where the handle rests in my palm, so the slippery nature of the polished handle has never given me any problems. On a flat-handled "stock" AFCK, though, I would prefer the rough texture of the factory G-10.
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-Drew Gleason
Little Bear Knives
