>>7922892I think in some ways it might be a bit difficult to differentiate between "best" and "favorite" unless one has literally bought everything. Perhaps "best" might go to something of FansToys -- Grinder, Terminus Giganticus, and this years' Road King are strong contenders; even if I only own the first one personally. DX9 could be a counter with their Gabriel. I'd also want to nominate ToyWorld's Constructor, but for as good as the gestalt can end up being, there are far too many & various documented issues with the individuals (I have one personally to one of mine) that I just can't feel happy with that. Similarly with Zeta's Armageddon the combination is quite something, but even if they don't have QC issues the individuals aren't strong together, at least as robots (plus the frustrating aspect of Brawl's treads). The Bruticon version certainly gives 4/5 better colors (I still think dark green Brawl looks best), but it's not really a fix to their looks.
On a realm of "favorites" I would probably list GigaPower's Gigasaurs as a collective, Master Made's Odin, Fans Hobby Power Baser (and now quite more adding in God Armor), and for being something just a little different TFC's S.T. Commander.