actinics will give you a better effect as compared to blue only.. have a mix of actinic + blue and you will see glow of pink, red, orange, and greens.. having blue only will give you a blue-washed effect that only enhances greens..
btw, blue tubes have a higher PAR than actinics.. actinics is for aestatic purposes mostly.. but its a well trade off for the effect you can get, in my opinion..