Sand beds: What do you need and why.

[Aquattro]

So, again the topic of sand beds comes up. Here's my take. I started in this hobby 10 years ago, when the DSB was the rage. I started my 75g with about a 5" DSB, using the new and wonderful oolitic sand. It was great. In very little time, I had a fully stocked SPS tank, no measureable NO3, and things were growing like crazy. For a while. Actually, pretty long while. But, about 4 years into the tank, things started going bad; wafer algae, valonia, all kinds of stuff I couldn't ID. Then dinos. That was fun. It was suggested that I swap out my sand, a third at a time. Well let me tell you, after the first third, I pulled it all immediately as I felt really bad for my fish. This sand was the worse smelling, foulest substance I've ever come across (at the time). I replaced it with about an inch of sand, and slowly, but surely, my problems cleared up.
Next wave: Suddenly, about 5 years ago, people started removing sand completely. OMG, you can't do that, what about nitrates. Well, I tried it, with a new setup, same 75g tank. I added about 65# of rock, 8000+GPH flow and away we went. SPS growing like crazy, colors were unbelievable and best of all, 0ppm NO3. Zip. Nothing. So, in my mind, good quality rock (as defined in a thread I posted within the last year) is as good as having sand, well, without all that yucky sand.
So, today. My current tank 90g, 125g sump, with 70# LR. I have added about 2" of sand, the courser stuff, just for appearance's sake. I have some diatoms (tank had a rough start) and I have a bit of clumping, not sure why yet, but still, my NO3 is 0. No, I haven't been using the same test kit for 10 years

To my point. Is having a sand bed good or bad? Is it good to look at, or is it serving a purpose, and if it's serving a purpose, what is it? No, please don't say it adds Ca, it really doesn't in any amount we care about. Is having a shallow bed bad, or just not as good as a deeper bed? Assuming a deeper bed is good at all.
Honestly, if I thought my rock would stay up, I'd pull the stuff tonight.

so what does everyone think about sand? Do you use it? If so, how much and for what purpose? If you don't, do you miss it? Why or why not?

Ok, go!