I've never personally seen problems involving leaks on the second generation G5's LCU. By then I suppose the problems had been sorted out.

One thing that might still be a problem is the use of ROHS solder and the heat given off by the memory controller until it finally detaches and renders the board useless. Again, I've never used a second gen so I can't say first hand but it always seems when a G5 diesn't drown, it dies from BGA contact failure.