[mseepman]

Well, it seems you've thought a lot about this already.

In regards to optics, just note that 40 degree optics really tend to spotlight the LED's so I would consider doing a bunch of 60's myself. If you go with fewer drivers..you need to do a little more detailed wiring to include fuses and resistors. When you do that, you will need to balance the strings, (move some LED's around) which is really tough if you use any method other than screwing the LED's to the heatsink. I tell you this because screwing them in means you need to tap the heatsinks (a bit of work).

As for controllers...I think the Apex lite can use their 1-10V add-on and it would be cheaper.

I'm a huge fan of LED and will be doing one of these myself with 180 LED's or so.