I'm not a fan of HAVING to remove the heads to transform and hoping the cockpits and such are good enough storage -- Skullcruncher's rubber plastic back panel wasn't super secure, and Perceptor didn't even have storage iirc (and then there's Wolfwire's odd breakage situation). To be fair, the rest have done very well with this.
But I like the play pattern overall. Little pilots with cockpits in every vehicle, lots of fun. While I'm not wild about non-Headmasters being turned into them, that just expanded the play a lot, and it does show a commitment to the gimmick that's the strongest out of the trilogy (but then POTP was basically "let's do a little of whatever"). And having some sprinkled-in lore for skirmishes (the box sets) and power-ups was better imagination fuel than the lower-key IDW take.
The toys have some of the best balance of interesting transformations and non-fiddly engineering we've gotten. Plus some of the designs were just great (the Jumpstarters have aged very well).
If they wanted to reissue de-Headmastered versions of some of these I'd be into it. But first give us a complete Horri-bull.