One of my clients uses a handful of EC2 instances with an ELB and RDS. We started off using MySQL RDS for a couple years and we migrated last year to Aurora. I'm not sure what you want to know, but honestly I have nothing but good things to say about it.
I'll be the first to admit I'm not the smartest guy in the room when it comes to database administration, so it's entirely possible that it wasn't as performance-optimized as it might otherwise have been if I'd set it up on its own EC2 instance and fine-tuned the configuration, but that's precisely why we went with RDS in the first place - less concern about screwing the pooch on the configuration/setup. We only had one issue the entire time we were using it, and that was my fault; a rogue script was logging like mad to a table and it ran out of space, causing me to have to up the size of the disk (and enable better monitoring).
It also is quite nice having nightly snapshots setup for you, along with a configurable maintenance period during which downtimes can occur. Granted, that's fairly trivial to setup for yourself, but if you're going to use a service, might as well go all the way :)
The only thing I would note is that we aren't using Forge, so this only speaks to my experience with RDS, not Forge + RDS in concert. Hope it helps anyway.