[bigron]

Bolt on jobs will normally not void warranty. plus if you are so skeptical about it , just remove the mods before you go in for service. Now coming to your question. Improving pick up and improving top speed ideally require different set of mods. For the exhausts i would suggest Cobra or Vance and hines full system. Add a fuel injection / timing box like a pc v or a bazzaz. This would give you best A/F mixture or closest until you get it (if) dynoed. If you dont want a full system just get a bolt/slip ons so you dont need a ignition module. I dont really know how it works for crusiers coz i dont ride them .Filters frankly go with any. I am sure all the regular brands BMC/K.N/PIPERCROSS or whoever makes them for your scoot. Lastly google is your friend. Read up , join forums , listen and watch videos and make up your mind.