Billy Goat

As i see it the resin pads should give better stoping performance but will wear out faster, ok in the dry . The metal pads have slightly less stopping power but will last longer especialy in wet conditons . Be carefull though some manufacturers specify the type of pads you should use i.e some shimano rotors should only be used with resin pads and magura say if you use non magura pads in their brakes you void the warranty.

It may be that your wheels need a little more tension now that the spokes have seated in . Was the wheel built useing a tension gauge , to ensure even spoke tension ? Noises on bikes are very tricky to sort out its often a process of elimination. A very common source of noises on wheels is the quick release skewer , if not tightened suficiently they can cause alot of creaking and cracking.