I perfer to use quads...
I love that they have the clear lid, so that I can see the shades easily. They are great if you are traveling, and small enough to drop in your handbag, if you need to. I use the use the circle labels, write the name of the shade on it, and stick it on the back of the quad where each shade is so that if I need to know the name of the shade I don't have to take it out of the quad.
I purchase eyeshadow pots from the CCO only, where I can buy them for about $10 ea. I never buy e/s pots from MAC unless it is a LE e/s that I absolutely love. Usually, I back to MAC them with the pots from CCO.
My advice to start your e/s collection is to frequent the CCO near you, and pick up the e/s you like. Keep an eye out for the new shipments. Also, MAC does a Friends and Family sale at least once a year, sometimes twice. I would try to get the rest of the shades at the sale. Get the pans instead of the pots to save $$.