The Insider sbs has a 23mm diameter atty limit and a 510 that can break easily. The Balance sbs fire and +/- buttons can be hard to locate without having to look for them, it holds attys up to 25mm and can used as an 18350 or 18650 mod but it's too small and uncomfortable to hold in shorty mode.

I prefer the Flexy which is more comfortable than the Balance thanks to it's ergonomic design but it's limited to 22mm attys and the ends of the =/- button sticks out which can be slightly uncomfortable for some. So if given a choice I'd get a CinqueTerre first, then the Insider, the Flexy and lastly the Balance.

Agreed, the Penon mod looks meh. Nothing new or exciting about it.