As many have advised before, strobes usually outlast your housing and camera so it pays to get something a bit more up market, albeit more expensive,so you can transfer it to your next rig. Also as you have a compact setup a high performance, compact strobe like the S2000 makes sense, particularly if you're traveling.
I used to have a DS51 with my first Canon compact in an Ikelite housing, but sold it with that setup at the same time I upgraded to a CanonS95 in a Recsea housing. I bought first one then a second S2000 and was very happy with the performance of the whole kit.
Now that I have an Olympus EM-5 in a Nauticam housing I will most likely upgrade the stobes to Inon Z240s.
See what I mean?