I have a tetra and oly 3040. I don't have the wetmate lenses (wish I did) and I used my own strobes, not a package.
shutter lag is very manageable, particularly if you keep tapping the shutter button to keep the camera warmed up on shutter and exposure. With slow-moving subjects, it's pretty easy to manage it while you are framing and composing. On fast moving subjects, it's tougher, but at some point, even with film, you are relying on the timing of the camera's winder and hoping for the best.
Manual exposure is the only way to go with strobes. It's not hard at all. I try to keep my shutter speed at 1/125 or 1/250, to stop action or sunbeams. After that, I fire a few test shots when I hop in, on initial decent, to set f-stop. You learn from experience what color blue on your lcd will produce the blue you want in your final picture. After that, you just tweak your settings as you go, up or down a stop as the sun goes in and out, or you go deeper, or you want more depth of field, or whatever, and you adjust flash strength as your subject changes and you mess up. Easy and fun.