I was also looking at the 10bar housing previously ... not for the LX3 but for the GF1. In the end, bit the bullet and got the more expensive seatool housing.
1. What i did not like about the 10bar is the single rotating button (button 4 in the manual) used for controlling the 4 way cursor.
You got to rotate it , press it ...and rotate it back to the AE ...etc. Just way too much task loading underwater ... it should just be a simple 4 button to the corresponding buttons on the cam
2. I cannot really tell ...but from the looks in the manual, it does not seems to have a transparent window at the cam flash position, which means that you will not be able to use fiber optics for slave trigger the strobes. I guess the advantage of using fiber optics is that it does not need additional bulkhead connector ...which is another flood point and another cost item.
The advantage of using the bulkhead is that it can probably use TTL to control the strobe power. But different strobes has different protocols for controlling TTL, as such, you got to get the correct bulkhead for the correct brand/type of strobe.