The WH12LS39 is essentially a WH12LS38 with M-DISC support.
Both are good drives and the performance of the two are comparable. The biggest difference is that the LG writes to BD-R DL media at 12x and the Lite-On at 8x. The IHBS112 also supports all of Lite-On's various technologies and does write quality testing, etc.
"Blu-ray is just a bag of hurt." - Steve Jobs