Difference 175MH vs 250MH

[BCOrchidGuy]

I'm about ready to order my tank, 60x24x19tall. I like the 24 front to back for aquascaping etc. My question is, should I stick with the 175 watt MH units or should I go with 2 x250 watt MH. I plan on keeping mostly soft corals but some LPS as well. With the 19 inch depth I think I should be just fine with 175s but I thought I'd ask. I think given the 5foot length the 4 foot MH fixtures should work out fine, I can center them and keep a colt or such on each end.
I'd like to only set this up once, I can't tell you how many times I've set up a tank and then started changing everything around. My 90 did well with the 175s and I'd not keep anything in the new tank that I didn't keep in the 90.

Thoughts?

Doug