I’ve been lurking on this thread for tips from the first post because I was signed up for Barry-Roubaix this year. I wasn’t going to chime in but since MuddyPuddle wasn’t able to race I figured I’d throw in a blurb about my experience. As a note, this was my first B-R and actually my first ever gravel ride so I don’t really know what I’m talking about. And I did the 62-mile SRAM Killer course, not the PsychoKiller.
Obviously I don’t have much to compare it to, but it was awesome! The weather was great, the course was in fantastic condition, there were a ton of riders, and it was well organized.
I’m a very low-level recreational rider and triathlete so I just kind of slotted it in as B Race during my general build phase with no specific preparation or goals. My pre-ride and in-ride logistics were terrible, and my bike prep was not good either (coulda used fresh tires and bar tape…and bottle cages woulda been a good idea 
…) but physically I felt great.
I was worried about the climbs because there were so many and so punchy and I hadn’t done any outdoor riding yet this year. But with nothing other than 3.5 months of indoor TR workouts I ended up feeling really strong on the hills and that’s where I made up the most ground on other riders. I mean, my segment results were abysmal objectively, but relatively speaking I was way stronger on the climbs - especially the longer climbs - than on any other segments. Especially the Three Sisters and The Wall. So that was awesome. Way to go TR.
Other than a crash around mile 18 on Sager Road and the aforementioned logistics issues I felt like I had a great first B-R experience and really was pleasantly surprised how well TR prepared me for it. Kudos to TR and I highly recommend Barry-Roubaix (as if it needs my endorsement, right?).