i don't know anything about the SD set up but here's my big race experience

i ran disney in Orlando in 2013 (the year before they cut back the entry numbers - approx 25,000 runners i believe) and there were definite bottle necks at some spots to the point where we had to actually walk.
it was confirmed in the first 5 minutes it wasn't going to be a PR type race so i just ran it with my friend and we had a blast taking our time.
try to get in as fast a corral as possible. i was supposed to be in "B" but my friend didn't have a time submitted so we got bumped back to E and there were people walking 4 wide less than a km into the race.
my race was a staggered start so we didn't actually start running until a half an hour after the race officially started.

Also no experience with RnR SD, but last fall I ran the Chicago marathon. Took awhile for me to get past the start line, but I prepared myself for that going into it. During that time, I really just did my best to relax and stay calm - chat with someone, take some photos, visualize yourself crossing the finish line! Honestly, once things got going, I never felt crowded, and there were 40,000 runners! I have felt way more crowded at smaller races, as they tend to be on smaller roads/trails and are sometimes not as well organized. Don't sweat it too much, as the RnR organization is well experienced in crowd control. Hope you have a blast!!

I ran the SD Rock n' Roll Marathon as my 1st (and only, 2nd will be Sunday) marathon but it was 12 years ago and prior to them adding in the 1/2 marathon option. There will be a TON of people and thus plan for more time for everything (bathroom, getting your bib at the expo, the start line, etc). Also, make a clear plan with your family on where to meet after the race. They have huge "family reunion" area set up with letters on tall polls. Pick a time and letter and have that be your meet spot. Even if you are running together there is a chance you will lose each other.

It takes a long time for all of the waves to start. So if you are starting with the 12:30 group it just may take you 30-45 minutes to get to the actual start line (i.e 10 waves in front of you with 3 minutes in between start times would take about 30-35 minutes for everyone to start in those waves ahead of you). Your time will be chipped though and your actual time won't start until you cross the start line. If you plan on actually running/keeping a 12:30 pace then you are probably good in that corral/wave. If you are trying be conservative and generally run faster (i.e 12/11:30 pace) then you may be better off trying to change to a faster corral.

You should have awesome crowd support and hopefully great weather. Enjoy!

Make sure that if you are planning on running together that you wear a color that will stand out. I ran a smallish 5K a couple of weekends ago (5,000 run/walkers) and because it was the Angel's race everyone was wearing their race shirts. The hubby and I wore our normal running attire. Really helped that he was in white in a sea of red when we got separated due to walkers, slow runners.

When I ran surf city (tons of people) hubby was able to find me because I was wearing grey capris and the majority of other people were wearing black.

I will sometime get a sweatshirt at Kmart or goodwill that I will discard at the start. Often races will have a pick-up and donation to goodwill of everything that gets left (although you might want to verify that for the RnR San Diego). It will be chilly (okay...I am a CA resident) in the morning in San Diego.

I'm from the area. Although I've never run RnR I've done a couple of other popular races in SD. Give yourself plenty of time to get to the expo to get your bib, as it'll be a pain to park. Get to the start line early as well as the parking will get more difficult as the morning goes. The morning will be chilly but a lot of people actually have issues with the heat during this race. You'll be standing around for a long while before the start so keep sipping on water and hydrate at every aid station if you're not used to the warmer/humid weather. If you feel you're too far back in the corrals you can always sneak further up. I like to start in the slow corrals though so I don't go out too fast. The RnR races are generally very well organized though and have huge alphabetized meeting areas from A-Z so you can plan to wait for friends ahead of time. Don't bother with a drop bag, it's always more of a hassle than it's worth at these big races. Check out the Ghirardelli Chocolate shop while you're in downtown SD

I've run the full at RnR SD the past two years. For the starting line questions, you should realize you can't park at the starting line and it is not the same location as the finish. You take a shuttle from the finish area to the park which can take almost 30 minutes. Normally conditions are warm enough you don't need any throw away clothes.

I haven't done the half but I've heard the course is real nice and fast. The last 3-4 miles you are running alongside the marathoners and it is a huge mass of people. There are 3-4 traffic lanes dedicated to the half and it looked like a solid wall of people coming down the hill. I do not know what pace group that was so your experience may be different. The finishing area is huge but there are so many people wandering about with no idea of where they are supposed to go it can be a bit of a mess.

I have run several Rock n Roll races. I really love their. Yes, they are a little big but the crowd typically thins out as people get through the start. They have really great course support and tons of people are out cheering you on (at least in Savannah and New Orleans).

I stay warm at the start line by wearing a trash bag.

We are doing the RnR in Portland in May.

Enjoy the race...but one thing to beware...some groups (not affiliated with the race) will have water stations and will also include beer. Could be a harsh surprise. HAA

LA Marathon was my first big race and I went into it as with a Prom attitude: relax, have fun, enjoy the sights, crowd, and experience. Save your PR efforts for smaller races.

Ask friends for old clothes they are going to get rid of to wear while waiting for the start. I still have my old clothes from my obese days, so discarding those at the start of a race is pretty rewarding.

I never thought I would run a RnR event because of their recent problems in the courts, but the recent running cruise I booked included RnR Seattle as part of the cruise, so I decided to part take in June.