so which hits harder and is the better to RTL with
Brick for sure. I'd suggest the Flip. For me the Twist is big and wide open and requires big glass to work well and it's challenging to scale down; otoh, it's also a fantastic injector bowl. The Flip is more restricted but seems to work easier anywhere.
I also use the Lotus more than either of those, but not as much as some other brick-style bong vapes. I feel it would be more challenging and more harmful to the cap to try to go as big with it as you can with the Twist, but it is plenty powerful. In use you can get great results from any of these, but the Lotus takes butane fumes out of the equation, if that's a concern.
There are a ton of brick-style bong vapes out there that are arguably better performers than the bong topper SBLs: Kalu infinity, Couch Log Steamwhistle, Dreamwood Switch (and any of the DLXs), and the Retrosteam Diamond is easy to use and hard-hitting. Some are very open and some are more restricted. Then there's also the Lamart Piro, which is among the easiest, most controllable manual vapes and also hits hard. With the bricks, they pretty much all hit hard, so other factors may shape your choice.
Of your choices, the Twist is probably the one most capable of really going big, but others will cover the use-spectrum more completely.