I owned a H16 and still own a 5.2 (which is for sale incidentally). Some remarks:

The 5.2 is faster. Until the wind gets nuts in which case the H16 can still sail while the 5.2 stays ashore.

The 5.2 is more stable. H16 are pitchpoling machines. They need taming! One you tame them they are a heap of fun to drive at the limit...

The 5.2 will support more weight on board.

The 5.2 will tack not matter what the wind or sea state. The H16 will do the same as long as you know what you are doing: weight placement is paramount on the H16, less of an issue on the 5.2

It is way easier to climb aboard a H16 than a 5.2 after a capsize recovery.

Contrary to what flying_dutchman said I've sailed my H16 solo without a jib, and it works just fine, you just have to reduce the rake quite a bit. I've also sailed the 5.2 in the same configuration (the overlapping jib interferes quite a bit with the spi I had installed) and it works okay.