When I 1st started out with the 464 i tried Eco's, LX's, HTP's, CD's & RRD's...I use 3" diameter metal tins and found the CD's to be superior in just about every way for me...sometimes i wish there were "in-between" sizes but generally they work really well for me. Depending on the scent, I use CD 10, 12 or 14 for my tins. I am about to start testing the "700 Series" wicks, just to see if they are better. They come in a million sizes! HTH!!!