Determining what type of buffing/ polishing machine you should buy has never been an "easy" answer for anyone making that decision. It comes down to these factors listed below, and they are in no particular order or "weight" to their importance, but for everyone you kinda know what is important to yourself as a detailer to determine that.
1) Initial cost. Let`s face it, COST probably determines a lot of things and the proverbial question of "How much do you want to spend" in this buying/purchasing decision is important. Everyone has a budget or set amount they are willing to spend.
2) How often are you going to use it? Everyday use for a professional detailer is much different for a hobbyists who may use a buffer once or twice a year.
3) Your personal skill level and ability coupled with buffer usage experience. Starting with a rotary may not be the best choice for a beginner UNLESS you are willing to dedicate the time to learn how to use it. Just because you can pick up an electric guitar does not mean you can play like Eddy VanHalen and even if you practice on the guitar, you may NEVER be able to play like Eddy (sorry to bust your Guitar Hero bubble!)
3a) What type of buffer do you want to learn or have learned to use:
a) Rotary
b) Dual Action-Random orbital
c) Direct Drive Random orbital
d) Opposing dual-motion Rotary, AKA Cyclo, although technically it is a Random Orbital
3b) What type of power:
a) Corded electric
b) Cordless rechargeable battery
c) Pneumatic, which everyone forgets, but those of you in body shops could not live without.
3c) If it`s electric, what is the wattage or amperage power rating?
3d) If it`s a rechargeable battery, how long does the battery last under full power, and/or how long does it take to recharge?
3e) What are the RPM`s or speeds (oscillations per minute) it can operate at?
4) If it`s a Dual Action-Random Orbital, what operating orbit size:
a) Long throw (15mm or 21mm)
b) Intermediate (9mm or 12mm)
c) Short throw (8mm or under)
5) Can the buffer/buffer do correcting AND polishing, or just one of those two, OR will I use it only to apply waxes, sealants, or All-In-One Last-Step Products?
6a) What size(s) of pads will I use or can I use the size(s) I have from a previous buffer?
6b) Can I change out the backing plate to accommodate different pad diameters?
6c) What pad types work best with the buffer Or will it accommodate different pad material types of:
a) Low profile foam
b) Dense closed-cell foam
c) Microfiber
d) Wool or foam wool
e) Cotton chenille bonnet (those of you with Wen or Craftsman buffers know what I am talking about)
f) Cleaning brushes (Don`t laugh! They makes special 4" diameter brushes that can be screwed on to a Porter-Cable DA in place of the backing plate that detailers can use to replace hand scrubbing!)
6) Ergonomics and machine weight
7) Buffing machine manufacturer`s:
a) Reputation for reliability and build quality,
b) Warranty,
c) Service and parts availability.
I have not even mentioned paint types (old lacquer, single stage enamel, Emron, clear coat) or clear-coat hardnesses or material types (paint, plastic, gel coat fiber glass, chromed metals, polished aluminum, or the ever-present carbon fiber) that you may be using your buffer/polisher on.
So once you have that all figured out and made your assessments and evaluations, let us Autopians know which buffing/polishing machine(s!) you decided to buy and use.