This seatpost by DaBomb comes in the following seat tube diameters: 27.2, 30.0, 31.4, 31.6. I was forced into buying the 30.0mm size because of a recent Viper frame I bought. Nevertheless, I was very suprised by the simplicity of the clamp mechanism. If you swap saddles regularly or get easily peeved doing so, this is the one post for you.
The top clamp hinges back, you can then easily remove the two clamp pieces altogether, fit them over the saddle rails and flip the top plate over again. It’s then a simple matter of tightening up a single bolt. The saddle angle is infinitely adjustable. The size of the clamp mechanism isn’t too great either, meaning there is a fair amount of fore-aft saddle adjustment too.
The post measures 350mm long, including the head, so it’s an intermediate length good for either road or MTBs. The only down side is that this post scratches way too easily. It’s also pretty hefty, not that that really matters for an entry-level component.