I'm not an exprienced photographer. I have a C-8080 & the PT-23 housing.
I bought the INON Z-240 and it was delivered today. It's my first strobe. It wasn't cheap. INON's are compact and light weight. They seem to be designed especially for Olympus cameras. Ease of use is the main reason I went with INON.
Tonight, sitting on the kitchen floor with the lights off (pitch black) and the focus light on, I've taken a dozen or so pic's of my feet and a few of a vase. Everything set to auto and strobe on S-TTL.
I used the .5 difusser with the red filter over the focus light. I haven't tried it without the red filter yet.
The camera focused faster than I anticipated. I didn't time it but would estimate 2 sec. The pic's were bright and completely illuminated but not over exposed. I'm pretty impressed. I going to take a real close look at the pic's with PhotoShop in a little while. That should reveal a lot.
Unfortunately, I won't get it underwater for 3 more weeks when we dive the Oriskany in Pensacola.
The Z-240 has the Nikonos connector and a GN of 24. For $200 less the D-2000 has a GN of 20 and no connector but all the other features. While the D-2000W (or Wn) is said to be dropped from the line, Backscatter said the are still available. The "W" gets you the 5 pin Nikonos connector for TTL. It's about $75 more the 2000. I think the Z-240 will be worth the extra $200 only if I upgrade to a DSLR in a year or so. If I don't upgrade I've probably wasted that money.
So... I guess I would recommend the Sea&Sea YS110. Just kidding!!!