I don't see when you are going to KW, so I can't tell if this is too late or not. At any rate, I have dived Looe Key with Looe Key Dive Center, so I thought I would tell you a bit more about it.
First of all, Looe Key is really nice. It's a deep spur-and-groove reef and as nice as any I've dived in the Keys. (Not that I am an expert, but I've done a number of dives in the middle and upper keys.)
LKDC is a bit of a cattle boat (when we went it was mostly snorkelers, just us two divers). Upon check-in you get/become a number, during surface interval they are selling hot dogs and drinks, lots of hyping the Tiki Bar, jokes you can tell are a routine, etc.
However, that said, once you accept it (or maybe you like that; is not usually my cup of tea), it's pretty fun. They were friendly and seemed to run a tight operation. The dives were beautiful. It's a three-tank day, which I think is perfect. They just putter over to another mooring ball for dive two, and then again for dive three, so surface intervals are about ten minutes. It works out because the dives are shallow. So you leave at around 10 a.m., get back in around 3 p.m. and you get in three dives.
I would not choose this sort of dive for my "regular" dive op; but I would go out with them again in a heartbeat to do Looe Key.
I think their base is around mile 25, if I remember correctly. So it's quite a bit closer than Marathon, which is where a lot of middle keys dive ops are based. That's around mile 50 or so. I think there is a bus that runs the length of the keys if you don't rent a car.
Blue Sparkle
PS: When I dived with LKDC I had a lot of leaking O-rings and one bad valve. Luckily I found the valve at the dock so they could load another tank for me. So you might check things before you leave the dock, just to be sure.