Do you need a hard soled boot or a boot that is slightly positively buoyant?

A top quality hardsoled boot from Fourth Element.

The Amphibian diving boots are designed for a diver who wants the ultimate in support and protection. A stable footbed and hardwearing moulded outsole make this ideal for regular shore diving. The Amphibian’s hard wearing optimised outsole gives a superior level of grip and maximum stability. This makes it ideal for shore diving, negotiating entry to the water especially over slippery rocks.

They are reported to be slightly positively bouyant which has made the boot popular with drysuit divers taking heavy fins to the tropics wearing 3mm wetsuits.  Without them, they would be struggling to keep their fins up. 

These boots are also becoming popular with boaties.  I personally use them when I am pedaling the Predator PDL or out on my paddle Kayak along with my Fourth Element Ocean Positive Hydroskin and Thermocline tops.