It is going to come down to two or three things at the end of the day. Budget. Upgrade or new tank. Hmm..just lost my train of thought and can't remember the third. Maybe fear of hitchhikers. Oh well.
Anyway here is the deal. If the budget allows then live rock will be the best solution. Sources like TBS (best on the planet bar none) while expensive ship fully submerged over night. Basically morning dive, collect, box up, drive to air terminal, board plane, less than 24 hours you drive to air terminal fright and pick up. Unbox, place in tank, and you are set. No mini cycle, or cycle, nothing. That is about as live as it gets. Better than Maxwell. Other sources like KP Aquatics, a bit cheaper, also dive, package, and ship over night to your door but not fully submerged. So a bit more of a delay, die off potential, and possible mini cycle as a result. Both are good sources and lots of threads here and other forums to support it. You will not get rock from the LFS or anywhere else (unless you buy from a hobbyist who is tearing down) that looks like this or has the quality of life on it. Just not going to happen.
Let us talk dry rock. Cheaper. Various sizes. Easier to aquascape due to hammer and chisel. Can epoxy together. No pests. Ships dry. List goes on and on. Depending on the rock there are some negative side effects such as leaching of phosphates well after the cycle. Pukani rock has this history although I don't believe much of that rock is available anymore. Anyway the rock will cycle just fine but the amount of time for the biological cycle to mature is going to take a lot longer post cycle. I'm talking months to years. Initially you will see the rock darken. Some ugly phases with diatoms, then algae, then even some correlline take hold. Take that piece of rock, pick it up, turn it, and now look at the back side. Back to square one with the rock looking like you just unboxed it. That is what I mean by saying the rock will take time to "fully" mature. I'm 2 years into my upgrade and only now believe it is mature.
But wait - live rock has hitch hikers. Sure, both good and questionable (bad). Good outweighs the bad at the end of the day and catching a few rogue crabs or snails is pretty simple all things considered. Couple nights and you will be clear. Besides if you look at dry rock (and I just went through this) unless you sterilize every fish and coral chances are still there that you will introduce something you didn't want. The fact you introduce a coral, regardless of source, means you are at risk. My opinion - this is a moot point.
There is another option regarding dry rock. If you are setting up a new tank you could very well order dry rock today and cycle in parallel while shopping, ordering parts, and setting up the display tank. This could take a while so in parallel you basically order a rubbermaid stock tank, the rock, bottle of Fritz or Dr. Tims, and cycle the rock while working out the tank logistics. You do not need a skimmer or lights. Just the stock tank, power head for flow, and maybe a heater. You can test water, change water, and let it mature. Once your tank is set up then place the rock and Bob's your Uncle. Instead of fresh out of the box rock you have rocks that have been aging biologically for months...
TL;DR; Both have their places. Upgrade, budget, use live. New tank or large tank dry will work. Try to cycle in parallel to reduce maturity. Dry rock takes a good long while to mature if we are all being honest.
Best of luck. Oh - BRStv has a video on dry rock, Pukani I think. How to clean, phosphates, etc.
