I voted for the bespoke technique. My primary reason for collecting transforming toys is the engineering itself. Having a combining toy is a very complicated project, the more you can tailor each part of it specifically to the team as a whole, the better the final outcome will be. I also hate parts-forming, and the scramble city style almost requires it. The MMC combiners are my jam, that's how I want to see combiners tackled in the future. This does get complicated when you talk about a main line toy though. Since specific toys only stay on the shelves for so long, a average kid won't have the luxury of getting a specific set. So having them being compatible over an entire line, or multiple lines, greatly increases the chances of a average kid getting a complete combiner. It also increases the play value of the toys. The more compatible things a toy has with other toys, the more ways you can interact with them. So I can see the upside of the Combiner Wars style of toys, but selfishly I'll always want the bespoke system.