Well, I can say that I own the cooler master and I think it's pretty awesome. It has its ups and down just like everything.
Pros (for me):
-Clean minimalistic styling with a few accents
-8th expansion slot
-Room for tons of large fans
-Has the dock on the top (never used it though :-/)
-HDD racks are modular
-Room for Cable management behind the mobo
-Not enough room for cable management even with a modular PSU...
-The GPU card holder is more of the hindrance than help
-The 80mm fans you can buy for behind the mobo tray and for the GPU holder are an odd size. Kinda pissed me off, but whatevs (I bought mine at launch and made no mention of it).
-No USB 3 support
-Wish it had other features like the latching doors like the 600T and more than 1 SSD adapter (or some other work around like the 600T).
My roommate just picked up the 600T so I've had the chance to compare the two now first hand. It's a solid case. The door latches are awesome, comes with a little more space behind the mobo tray than the 690II, USB 3 (sort of, just includes a cable to route it to the front since mobos don't seem to come with it on the PCB), the HDD trays actually have holes in them already from mounting 2.5" drive (They're kinda flimsy, but they work), built in fan controller for 4 fans. I like it a lot but for me personally if I were to build another mid-tower I would wait for the Corsair 650D. It has the minimalist styling I want on the 600T chassis (with all the same features, well... interior features that is).
I've never seen or touched a Lian Li case personally. They always look, I don't know, more industrial grade to me. Their owners seem to be die-hard fans though, which says a lot to me.
Hope this helps, -Chizel