I need a new shoulder-clip light (or two)

[Mr. Sunday]

what's the appeal of a light with a battery like that, as opposed to a light that has external battery contacts so it can be charged without opening?
There are some like that too, right?
I understand the corrosion potential, but if it's a quality design.... that shouldn't be an issue
Seems to me that every time you open it you increase the potential for o-ring wear or damage...or a little piece of something dirtying up the seal.

Personally, I don't want a fixed battery.

I prefer to be able to use new batteries as needed rather than having one degrading over time inside my light. Also, I can swap to a fresh battery immediately after a dive to be ready to go again without having to recharge. I can use rechargeable or standard alkaline too. Options.

I have never had a light flood so opening is a non-issue for me. I have heard of corrosion to the USB ports as you mention though on that style. To each their own.