I'm a new LED500 owner, having recently taken advantage of the aforementioned deal that DiveRite Express is offering.
I was also looking at it for similar reasons to yours, i.e. as a general-purpose dive light, not specifically for big-time light usage like cavers need, but for peeking under reefs and ledges, minor wreck penetration, night dives, and an occasional cavern. So I wanted something configurable either as a standard handheld or canister/Goodman-style.
I have only used mine a few times since purchasing, but I've already tried both configurations and I think you'll find it perfect for these kinds of applications. And the battery life seems to be great as advertised: after about 8 hours of use, I am still not noticing any decrease in output.
Minor gripe: I do wish it were a little easier to mount the head to the Goodman handle in canister mode. The design requires a small-point Philips driver to accomplish, making it more difficult than I think it needs to be to switch modes - given how easy it is to convert the light itself.
Also, the supplied velcro-topped holster fits well and is usable for both modes, although when used as a handheld I am a little worried it could slip out unbeknownst to me and am thinking of ways in which I could tether it.
Like any general-purpose piece of gear, it's not as well-suited for specialized applications, but it seems to do what it does for the kinds of purposes you & I are discussing well and reliably.
>*< Fritz