AJ: Actually some/most (if not all) 5200K are coated, and all higher bulbs are even more coated/tinted. This tinting reduces the lumens substantlially. As far as Phillips bulbs go, 4300K are the non-tinted ones and put off the most lumens. IMO the color shouldn't make a difference, that's all color temp bs (as you stated, yet talked about color).

Just to point out though, normal halogen color temps are no where near 4300k unless very tinted, reducing the halogens output quite a bit.