40 breeder? Use the 250 and the t5s. 40 breeders are tougher to light end to end with mh since most cover about 2'x2' area. You may not get enough par with one 150 depending on how many t5 you use. 2 150s would be good also. All sps I'd err on the side of more light.
With a 250 you could raise it up a little higher for more coverage and less heat.