I guess my first question to all of this is to ask what kind of money are you looking to shell out for this tank? OM are very nice, but also costly, as are vortec's and tunze's. Koralias aren't controllable, unless you buy the (much) more expensive ones. The MJ mods are pretty nice...a little bulky, but overall give great results, and as Roland noted, at a pretty low cost. I had a closed loop...but barely ever used it...however, I still think they are a good idea if cost is an issue. If you run a pump like a Reeflo Dart through a manifold, you could probably go with 4-6 holes and be pumping out about 400 gph through all of them. At 150 watts, you're a little less economical...but the pumps are very well made, and deliver great results. The other thing to consider with so many holes is that when all your plumbing and locline is in the tank, you're probably looking at about $200-$300 for plumbing and $200 for a nice very gently used pump. That may seem like alot, but considering it's the same price as a single Vortec without the battery backup or the controller, it's not such a bad thing. You could also add an OM to the closed loop OR return without anything bad happening. Of course, to make that worth it, you'd want a smaller pump, and more holes in the back of your tank.
I use 2 K3's and a K1 in my 60 cube, and I get pretty great flow with that. While people will criticize stationary pumps and get all excited about "random" (better termed alternating...random would eventually blow water right at your lights and create sand storms...random is bad...I prefer to be able to control my flow to some degree) flow, I've found that my flow is anything but constant since the slight variances with the flow coming out of the pumps is multiplied exponentially as they hit the glass and each other...and I get a nice range of flow at any given spot over any given period of time.
