Classics for me. Took a while to get to the end of my collection, but I love their: size - in my hand and on a bookshelf; scale; potential - so many characters left for third party producers to fill the void; and the amount of Decepticon toys actually balancing with Autobot toys (with MP, we're more likely to get Slicer, Dark Ultra Magnus, Dark Star Sabre, and Bugbite before seeing a new unique Decepticon mould).