Comes down to personal preference and your budget (don't forget to include things you may forget or under estimated in the budget). There are pros and cons of using both live from sources like Tampa Bay Saltwater or dry rock like Pukani (insert vender here). Fact of the matter is what starts out as dead and dry (Pukani) soon becomes alive. It just takes sweat equity and time. I've done both (live Fiji back in the day) and recently 150 lbs of dry Pukani (which is since alive) and while I personally enjoyed both I will not do dry again. Difficult has it is to say there is just too much bio diversity missing and being honest, which I should be, I'm a bit impatient and feel I missed out on a lot of good, and bad, hitch hikers.
I posted this elsewhere a while back but in 2000 I ordered some live rock from Fiji, Harbor Aquatics back then I think, and it was pretty amazing. It was shipped two day air I believe and wrapped in wet news paper. Not like the stuff TBS does today over night, but it was still alive and there was still lots of stuff wiggling around. In any case it did have a mini die off and ammonia spike because of dye off in shipping but the bio diversity on it was amazing and I still have the rock, and sponges, today that live on it. Over the course of the year I saw various forms of algae grow that wasn't brought in elsewhere. And while some good hitch hikers in the forms of snails I also had some bad crabs that took months to capture. While they wrecked my snail population and probably some other things I don't know about it was fun, in a weird way, to learn how to capture them without tearing down a tank. It really was a piece of the ocean in my living room in which to this day I remember my children using small flashlights with red lenses to see what the tank offers at night. Really educational and nerdy I guess.
Since then I've bounced around a few tanks due to a power outage in California in 07/08 (thanks Enron) and having my tank crash while on vacation so consolidated tanks into a 29 gallon bio cube. Later added a 2nd, then combined those into a 40 breeder the whole time using that same rock above and sand. Last year I've been slowly building a 210 gallon to move the 40 into and with two children in college I decided to use dry Pukani. Now - my original plan was to use TBS (Sorry Richard!) but I just couldn't wing it so dry it was. I ordered 150 lbs from BRS who drop shipped 4 large boxes with the goods. Now, some of these rocks are the size of front yard landscape boulders (ok, fishing tale and I jest) but to be honest 15 - 23" across with girth to match. Good shapes, a bit dirty, with some rubble. I got this. Pressure wash, load up in bins, add some tap water, add some bleach, soak for 24 hours with a power head. Dump water, add more tap water, more bleach, run another 24 hour bath. Dump that water, refill with tap water, add some lanthium chloride, power head, sit for 24 hours. Dump, repeat another 24 hours. Empty that, pressure wash, then introduce into tank to aquascape. Let sit over night, add some sand (Carib Sea pink Fiji (2 bags) with 4 bags of Carib Sea Florida crush coral mix), let that sit, then add RI/RO saltwater. Let that sit 24 hours, test Ammonia which should read 0. It did. This was back in February 2018. For the record the rock was moon base 44 looking type all tan, white, and bare to put this into perspective. I mean - clean more or less outside what the pressure wash didn't get...
Dosed ammonia to 2ppm, let sit for 24 hours, tested to verify, cycle started. Added bottle of Dr. Tim's one and only a day or so later to kick start bacteria. No lights, no skimmer, just return pump and tank with power heads (maxspect gyre XF250 and sea swirl returns). Tested Ammonia every 2 days to see how long it took to get to 0 then tested for nitrites. Watched that balancing act while things started to happen in bare rock. Finally Ammonia and Nitrites both reached 0 and Nitrates started to climb, cycle was done. This was March. So I then re-added 2ppm ammonia to verify it would process in 24 hours. It did. Cycle is officially done. Along comes April so I started the lighting, started the skimmer, and on the 15th I moved over my 40 breeder, fish, corals, etc. Tank is officially on its way. Now I can see clearly the difference between the dead / dry Pukani that I started with compared to the live rock I mentioned above. I mean it isn't really fair and all because the time difference but it was noticeable...
Enter today, May 15th. The tank is going through some diatom outbreaks which is perfectly normal and it is under control. Sand is clear, rocks have snails managing it, and there are no signs of hair algae. Tang, damsels, lawnmower blenny, and clowns are doing well and picking off the rocks when hungry and eating all food. I can now clearly see blotches of purple / coralline algae on the dry Pukain. See - this right here is why it is also a good thing, just as educational, taking dry to live. Anyone who passes the tank comments on the rocks that used to be tan, bare, white, looking like boulders from the moon and today saying how much different they look turning purple, brownish, darker tan, and blending in. I'm seeing bristle worms from my original rocks moving down lower to the sane. I'm seeing spaghetti worms moving about in the sand, biovalves on some rocks thriving, etc. There is just stuff growing on what was otherwise dead, dry, and bare rock.
So....I guess to close this wall of text there are valid reasons to do both. While I have done both, and actually enjoyed them (the cycle is really an amazing piece of science in our homes) I want to try TBS / Live Rock if I ever do this again. It is environment friendly, I think you get a lot of instant diversity when properly shopped, and upgrading tanks reduces downtime and lowers risk. I can't say for sure that will work for you - but that is how I see it.
TL;DR - you can't go wrong with either!!!!!!
