I need to transform them a couple more times I think, because there were bits of each transformation that I found fiddly or annoying. The combined mode is definitely the best, the individual modes have suffered a few painful compromises (particularly the rear end of Roadtrap's vehicle mode).

On the whole though, quite an achievement and I'd love to see more combining Legends like this. CW-style Combiners are super tired by now, but this is something fresher.