Yes. Years... as in two or more. It takes about a year for most tanks to fully cycle anyway (all the way to Nitrate and Phosphate control, not just Ammonia and Nitrite) and it takes even longer for bacteria and microfauna to establish enough in the core of the rocks and also consume the bacteria that is now dead that used to be alive when they were in the ocean. Without this, you can fight nitrate and phosphate issues for a long time.
You might be able to coat the outside in coralline in 6 months, or so, but the biggest value of the rock is on the inside.
You can get real fiji rock for about $3 a pound shipped if you know what you are doing, so how much cheaper can dry rock be? I imagine that a local store could get pretty close to this if you paid in advance picked up a few boxes off of the van from the airport.
If you are in this for the long haul, then get some good rock. It matters. Marshall Island used to be the best, but it is REALLY hard to get anymore. The stuff from Vanuatu is pretty good. So is tonga. Fiji is a good rock for the money. The dry rock, or stuff from the Keys is pretty dense and you will need a LOT more to do the same thing and take up the same room that good rock will do and tank - I have a basketball sized piece of Marshall Island that weighs 8 pounds (at 8.99 a pound) whereas the same sized piece of Keys rock weighs 32 pounds (at $5-6 a pound). In the long run, good rock is cheaper than cheap rock.
I have no used any Real Reef rock, so I have no idea how good it is with denitrificiation and phosphate exchange, or how it compares with cost-to-weight ratio. I need to try it out. I do think that the purple color is quite horrible.