I thought I would share my first proper set of large gauge conches! Generally, I only do one side, and once I did a tandem with 8mm (0g) jewelry but I still only pierced the one side (the other side was done by another piercer at the same time). I love doing this kind of work!
I did this set on one of my fantastic regular clients. Two 6mm/2g conches with glass.
Going this route as compared to stretching makes things a lot easier (and safer!). Healing these are pretty similar to healing a normal cartilage piercing. I recommend hot saline compresses, and chamomile tea bag compresses if scarring shows up. I've found that some people will experience no problems at all, but some people will experience prolonged soreness and off and on, and minimal scarring during the first few months to a year. Even after the piercing has healed, you can still experience off and on soreness. My conch has been 4mm/6g for years, and if I sleep on it wrong, I will have a little discomfort and soreness for the first part of the day.
If this is a procedure you're considering, please go to an experienced professional! Consider that this is a permanent removal of cartilage, and a permanent modification of the ear that will likely not return back to normal after removing the jewelry. Larger sized removal like this may also yield the results of some hearing impairment/loss when wearing certain kinds of jewelry (like eyelets/tunnels) or when not wearing jewelry at all. It's important to make sure you know all of the pros and cons before considering this kind of modification. Be safe with your body my friends!