But still - are FETs as easy to control in a current regulation situation? Also - are there many that can dissipate over 100W of power? I've never used a FET before to limit current and am not really sure how easy it would be to get a good steady current regulation from one.

I was thinking - what if I use a length of copper wire say 0.1 Ohm from each of the emmiters, the copper would naturally increase it's resistance as it gets hot and let less power through the transistor - so then it would have a semi dynamic leveling system rather than just a static resistor?