In short, it's a Houck classic worthy of the praise it has already received in its brief existence.
Somehow the lack of course fee or clubhouse makes the course seem like an ordinary city park course when you arrive. Perhaps this is also because the terrain and trees obscure all view of the course except for the first tee and practice basket. Hole 1 immediately dispels thoughts of an "ordinary" or relaxed disc golf round, with a difficult par 5 crossing the creek multiple times. I tried to put this in words with my title of "unassuming excellence." Your socks will definitely be knocked off, but simply by the golf (and beautiful surroundings, typical of this part of Missouri) rather than by frills, the obviously expansive grounds or water shots (e.g. Selah), or physical demand (e.g. Branson Trails, Orange Crush, Coyote Point at Lake Casitas, Sharktooth Mountain...).
It's strange to say this about a par 68 course, but one thing I love about HB is the fact that it has such great multi-shot holes while still including some fun ace runs and "hit your line for 2" par 3s. I think some courses try for too many par 4s and 5s and miss some of that line-shaping fun. My first round (from white) I ended up shooting 2 under par, but my putting was on and I was hitting my lines. I tested the blues for my second round, and I was 5 over after just six holes! I must have been tired. I liked 'em all, but here are a select few: I loved hole 4's straight downhill shot with ace run potential (parked it with a pured Pure). Hole 5 was one that I'd love to play again, requiring a decent initial shot to get above a rocky shelf and then leaving a tough approach. 7 (par 3) and 10 (par 5) both had downhill tunnel tee shots, of which I never tire. 10 required choosing between two layup zones, either of which gave good approach lines to the green. 15 was a tricky obstructed tee shot requiring you to get some decent distance before a tough uphill woodsy approach. The finale of hole 18 was possibly my favorite par 5 anywhere. Downhill tee shot, followed by the possibility of risking the OB creek bed for glory or laying up to the right. I went for glory on my 2nd shot, but barely caught the bed's lip and fell OB. In my case it would only have given me an easy birdie, but still... so close!
Like other Houck courses I've played, HB tends to provide a couple available lines both off the tee (hole 10's long tee was a particularly good example, offering a tempting RHBH sky anny or RHFH, as opposed to the tight downhill tunnel) or along the fairway. Great design, throughout, was impossible to miss. My impression is also that Houck likes to force some forehands (hole 13 practically requires a forehand). I benefited from having a decent forehand/backhand combination.
Part of what makes HB so special is that this land is available almost exclusively for disc golf, aside from an occasional dog walker. Quite simply, it's premium disc golf terrain with tall, mature trees (couldn't find better for disc golf), a creek and elevation changes, all of which are used to great effect by Mr. Houck. The reason for this land's availability, as far as I can tell, is that it's in a flood plain that precludes many other uses. When I was there, it hadn't rained for at least 5 days, but the stretch from 11 to 14 was noticeably affected by the land's flood plain status. Hole 11, in particular, appeared to be permanently affected due to the combination of water-rise and most-of-year shade. That shade is a dual-edged sword, providing an awesome covered fairway but also leaving a floor that is largely mud and bare soil (basically no grass). Even in the absence of recent rain/flooding, that fairway was pock-marked with grooves and ruts, with several puddles and muddy spots. I would imagine a TD being required to make some sort of accommodation for casual relief from these ruts, as my solid tee shot was spoiled by poor footing (that's my story and I'm sticking to it!) resulting in a botched, otherwise simple 180' to 220' approach. Holes 12 & 14 were fairly marshy but I was lucky to avoid the puddles, and the grass (open to sun here) alleviated some of the fairway issues present for hole 11. These issues must get WAY worse during heavy rains, but I can forgive that. I'd imagine it drains fairly quickly, though I worry about erosion damage to baskets, tees, signs, etc. At present, the local disc golf club (and City of Columbia) seem committed to maintaining the course, so I don't believe this has been an issue.
Though the course was surprisingly unoccupied, I met several locals. One guy had a starter pack and had ONLY played Harmony Bends in his first few months disc golfing. Wow! Imagine cutting your teeth on this masterpiece. It would be hard to play anywhere else. The fact that Houck's red tees are playable by such a new player, while the blues/golds would challenge disc golf's best, shows that Harmony Bends has something for everyone. The fact that it works for players of multiple skill levels (and fitness levels) is my explanation for its seemingly unanimous acclaim.
Rating: I really can't justify anything less than 5 for "best of the best." The flooding issues are my only complaint, but I view that as a calculated risk, and the course is better for it. This is not my number one, but it would be a happy day for disc golf courses everywhere when I could justify dropping HB to 4.5. To the City of Columbia, the local disc golf club, and Mr. Houck: thank you for the financial commitment, continued hard work, and dedication to disc golf excellence! Your efforts have not gone unnoticed.