That's interesting that you consider the Solo II to be the smoothest you've had so far – I mean it is kinda tame, yet my throat was always barking at me a bit (quite a bit actually) after a session with the Solo, just because it took so darn long to finish a bowl. The TM is considered to be a heavy hitter, but it's all relative. The amount I'd typically use in a Solo I would probably be able to kill in three hits at medium temps in the TM – so three hits compared to six or eight hits with the Solo, that usually leaves my respiratory system in a better mood after all. But even if you set it lower than medium to spread the session a bit (which works really well as mentioned already) the cooling unit prevents that hair-dryer-pointed-at-throat feeling that I get from the Solo. It's also an excellent device for on the go.
However, when it comes to the coolness ←→ vapor ratio, the Taffee Bowle wins in my opinion. The Bowle at „2” will give you dense vapor, but *super smooth*. The aggressive cooling does rob a bit of flavor in my opinion, though, the battery life and weird form factor makes it much less versatile compared to the TM too.