Are these lights worth the deal??

The Maristar has very efficient reflectors for the MH. The reflector is based off of the SLS Reef Optix III. The biggest factor is the choice of MH bulbs as many off them just plain suck. Then again there are a select few that have massive par/watt factors. Penetration for this fixture with the right bulb is easily enough for 24" deep tanks, while coloring up sps on the sand. With MH, I cannot stress how important the quality of the reflector is and how important the bulb choice is.

 

No, directly under it, the 4x39 will have roughly the same par as your current fixture. l had your current fixture on a 29g and it couldn't support a hammer coral low in the tank. Of course the hammer coral I'm referring too seems to need more light than some of my SPS for some reason, but still nowhere near as much as a clam. The 6x39 should be ok though.

 

Interesting, usually the MH T-5 combo fixtures don't have good reflectors. Good to know. Great point on the bulbs too, a 10K 150 can have more par than a 20K 250W. If your willing to live with the color, they can be quite efficient. Often the need for higher watt bulbs is so you can run them bluer.

 

Actually some of the top 150 watt bulbs with the high par are also higher kelvin bulbs. Problem is, many people who choose 150 are on a budget and won't spring for the high cost of the better bulbs. Here is a list of some of the better 150 watt bulbs that have some blue to them.

Iwasaki 20K (white w/ blue tint)
Iwasaki 50K (white w/ purple tint)
Radium 20K (white w/ blue tint)
Phoenix 14K (white w/ blue tint but more blue than others listed)
Aquamaxx 14K (white w/ blue tint)

 

These aren't bad for blue bulbs. Just looking quickly at Sanjay's data, I don't see all listed, but for the ones I do see, they are listed at 20%-40% (or more) less PAR than say a XM or Giesemann 10K 150W, depending on the bulb/ballast combination.

 

Who wants to look at corals inder a 10K (white w/ yellow tint)?

 

MariStar = high quality fixtures with good reflectors

You already stated having Radium bulbs for the halides. I think you will be just fine with this fixture. Just don't skimp on cheaper bulbs when the time comes to replace them.