You’re definitely thinking on the correct lines. On a cost per watt basis the hlg-185 is the cheapest. There are scenarios when it’s best to use a different model, but you can essentially get two of the hlg-185 which is 200 Watts in most applications, for about the same price as an hlg-320. Based on that, I always look for how the different led configs will fit the 185. In your case, running the 1212 at 1050ma meant you can squeeze an extra cob on there and take advantage of a little boost in efficiency. Not a hard decision to make at $9 a cob. If it were a cxb for instance that runs a little more efficient and is $40 a cob, it makes a little more sense to go with four at 1400ma.
The vero’s open up a different part of the game having 3 different voltage options and being a little better at higher power. The hlg-185 not the best for 4 of the 36v as it’s limited to 1400ma. Stepping up to the 240 would be necessary, but would leave some voltage available out there from driver. The 320-2100 is about a perfect fit. But running the 69 volt version two cobs fit about perfectly on the hlg-185 if you’re looking to crank out the Watts.
It’s merely a function of finding the fv of desired cob at given output current, and then adding up the voltage of desired amount of cobs, and seeing if there is driver they fit in the output voltage range. There’s obviously more to which line of drivers you want to use, but I’ll cover all of that.
I’ll be sure to tag you when I get there.