I use a Tubus Swing rack on the front of my hard tail. This rack mounts above the shock and thus has no effect on the handling of the bike. OTOH, the rack you mention (as well as OMM and others) mounts below the shock and requires the shock to move the weight of the rack/panniers as well as the wheel which can't be good for it. Or, more strictly speaking, the shock is operating between the momentum average (mechanically speaking) between your wheel/rack/panniers and the (leveraged) weight of the rest of the bike on the front wheel system. If the shock is locked out, well, then its just like a rigid fork.

If at all possible, I'd suggest the former mounting system.