As for my knowledge of braking, well I've been working at what was Girling for the past 15 years in their aftermarket braking and also race a a big twin classic sidecar (weslake) in the UK and occasionally road racing on the continent, so for what its worth:
Wavy discs are very much a recent trend and yes they can sport the benefits of reduced mass and yes you can expose a certain amount of surface area for the heat disipation but in reality the majority of road use would not subject the discs to the kind of heat cycles that would make any appreciable difference.
Yes you would get an increased rate of pad wear and there is always a question mark over the raw materials used in aftermarket product coming from China, not that I'm saying its rubbish but there is sometimes a tendency for inconsistencies in material content and you could never be 100% certain. I would suggest for general road use they should be okay but if you start to get any brake judder then the material has deformed and its surprising how only a miniscule amount of variation can amplify itself through to the controls.
By far the best material for brake discs is cast iron but for motorcycles you've got all of the related cosmetic issues but in the old days all brembo braked Italian machines had cast iron discs however they rusted and looked shite. If you wanted to be really flash you could go for a high silicone/carbon content which gives greater stability over the heat cycles.
We use cast iron discs that are drilled but the surface area of the drilling should not be smaller than the disc surface area as a blank.
The biggest gains in braking would always be in the friction material, racers will always spend on brake pads as the benefits in lap times are worth having. Again racing pads are a different game to road material as they require the heat for them to function properly and a good set of road pads should be more than sufficient ( I'd rather recommend the better ones than slag off the bad ones). Also you should change your brake fluid regularly as it is a key component in you brake system, we change it every 2 months for racing but still we only use a dot 4fluid just so long as its fresh.
On a totally different note I've bought a TRX (from a guy on the forum) and it is being delivered tomorrow evening - CAN'T WAIT
.oh and welcom to our place.!