My opinion and experience. I started reefing in 2000 when live rock and live deep sand beds were the push and made sense to me as an ecosystem approach. I started with 50/50 uncured Fiji live rock and dead coral/tufa rock. I cured/cycled in tank. "Hand cured" by pulling off rotting things, doing WC's to keep ammonia manageable. It was a small tank, 38 gallon. Main cure cycle was quick, but did have some ammonia bumps several months later, but was using cheap test kits. I was putting soft corals in this tank at month two AND getting into a routine of testing weekly, maybe a bit more and doing WC's every other week. I also started dosing kalk....I wanted to get the coralline to spread off the live rock as well as the tube worms, forams and the other micro life that utilizes calcium. I did have the typical uglies but don't ever remember dinos being a thing. By year two I had a nice tank of mixed softies and LPS that were growing I even had a rescue porites that was doing well before I upgraded at the beginning of year three.
With the upgrade to a 55, I got 30 lbs of Florida cultured coralline live rock, cured in a vat for a month or so. Upgrade went well, I had about a dozen urchins plus various red macroalgae, sponges, etc come on that rock. Then disaster struck, a heat wave struck that tank and nuked "everything". I recured/cycled the rock and had problems after that, but looking in my records several months later I was seeing pods and worms in my tank and one particular macro algae was taking hold that had come off the live rock and I couldn't manage it, urchins would not eat it and pulling it only make it spread since it was very brittle. It eventually went away. I did add a couple of pieces of cured Fiji live rock from a great local source and still have one of those pieces over 20 years later still with coralline coverage and a pair or large tube worms.
My routine maintenance faded for several years with upgrades, even with adding "live haitian rock" which was moist boat rock with the only visible life was fruit flies. Although that rock became live again when I downgraded to my current setup.
My current 29 gallon was set up in 2010 with the choice pieces of live rock I had, plus some dry marco rock. Around year two I had good coral growth, but also had hair algae taking over dry and live pieces.....neglected maintenance due to dating my future wife. The last few years I've managed the algae well and my marco pieces look like live rock and corals growth is great, dose kalk, mag and do occasional WC's. I even added some bucket cycled dry rock recently and it isn't really getting over taken by algae, a little cyano, but I did stir some things up when I moved things around.
I don't have experience with 100% dry rock so I can't comment on it's use, but one thing I haven't dealt with are dinos....maybe there was a little tuft of it when I was testing low nutes, but my guess it something ate it or out competes it.
The only "live rock" I've added to my system now would be the base of a coral or frag plug. I rarely dip, when I did I killed about 7 mini brittle stars, couple worms and pods. FWIW though I do have pests like vermetids and aiptasia, had them for years from previous systems. I manage the aips best with peppermint shrimp or kalk paste. I'm trying bumblebees for the vermetids, but may try coral snow.
I almost pulled the trigger on getting a treasure chest package of live rock rubble from TBS, but thought I still HAVE life on my rock now and corals are doing fine. I even found a brittle star in my glass scraper the other day.
