It seems that difference between "B" and "S" series of HP notebooks was never more distinctive then in recent period at least when it comes to quilt quality. HP Compaq 6735s didn't impress us but HP 6730b is worthy to represent its famous manufacturer. Big difference between those two series can be noticed after first contact. Chassis of HP Compaq 6730b is very stiff and whole notebook looks like robust and reliable piece of hardware thanks to roll-cage that is reinforced by magnesium alloy.