I love In N Out and have been eating there all my life (usually 3 or 4 times per year)...but I still wouldn't say it's worth the trouble you'd have to go through to try it on your DL trip.
I've had food from Five Guys and definitely think In N out is better...but as a PP said, my preference likely has a lot to do with the fact that I grew up eating it.
Something to remember...even the In N Outs that DO have indoor seating, they are ALWAYS super busy and there's often nowhere to sit. We have that problem with the one that is 10 minutes from our house and it doesn't matter WHAT time of day we go, it's always like that, from open to close.
Also, it's a very popular spot for people traveling with dogs. So, say you can't find a seat inside and have your food in your car or outside...it's not uncommon to have a dog relieving itself nearby - which is something that immediately makes me unable to finish my food. So, if we can't find a seat inside, we actually take the food home - no more eating in the car at In N Out. And even if you're not dealing with dog-potty issues, you'll almost certainly be enveloped in someone's cigarette smoke if you're trying to eat at the outdoor tables.
As much as I like the burgers there (the fries and shakes leave a lot to be desired, IMHO), I would never EVER bother going to one unless I was literally driving right by and it was going to be relatively easy to go. It's not worth a bunch of hassle. Just my 2 cents.
Hate to discourage anyone from trying something they wanted to try...but wanted to give an accurate account of what you're likely getting into before putting in all that effort.
