I decided to do Honolulu as part of my 50 states quest and a vacation celebration of 25 years of marriage. We stayed at the military hotel, so we were able to get a break in the price and stay out of some of the madness. Approximately 30000 registered for the race but only 22009 showed up to run and many of those were Japanese runners treating this as a destination marathon. The pros and cons were:
Pros
1. Lots of support on the course
2. Frequent water stops with water, Gatorade, sponges, and PowerGel.
3. Fireworks at start
4. No time limit
5. Nice medal and finisher tech shirt
6. Well prepared medical staff
Cons
1. Lame small expo with many booths having little running connection
2. No easy transportation to start or from finish
3. Bags with clothing needed to be checked day before race at finish line
4. Out and back 10 miles of course on highway with no shade that compounded high temp and high humidity weather that is common for the marathon
5. Insufficient portapotties and placed too close to start
6. Pace signs at start, but no corrals so many runners did not line up appropriately
7. Sold as destination run to many Japanese runners many of whom were not adequately prepared
8. Finish line poorly arranged forcing runners to walk long distances to claim medal, finisher shirt, and post race food.
9. Registration was over $150 unless you registered in the first few weeks or were a local

I recommend considering a marathon on one of the other islands or coming into Honolulu with significantly reduced expectations.

Marathon morning dawned cold (temps not far above freezing). Large half marathon field and much smaller marathon field. Course was through Chickamauga Battlefield. Marathon did two loops while half did one loop. Footing was a bit rough getting from start area to roads in park. There were three places where the loops for the marathon and the half were different. They were well marked but you need to be alert. Marathon sometimes aligns with prime foliage, but not this year. Spectators were few. Volunteers were many. Tech shirt was a bit bland. Medals and post race food were well done. Plenty of parking near start and finish. Needed to go to Chattanooga for hotels - about 10 to 20 miles away. Overall Chattanooga Track Club did nice job organizing this marathon.

This marathon is part of a series of low key marathons and half marathons put on in the Mid-Atlantic region. There were about 70 marathoners and 130 half marathoners (entries were capped at 200). Course is entirely on paved rail trail through woods near Potomac River and C&O Canal. Marathoners started 30 minutes before half marathoners and ran out and back twice. Since you are on the edge of mountains, it was gradual incline out each time and gradual decline back each time. Temperature at start was 37 and 65 at finish.
Pros:
(1) Small race in the woods
(2) Friendly runners and race directors
(3) Water stops with water. Gatorade, M&Ms, cookies, etc.
(4) Parking close to start
(5) Packet pick-up available morning of race
(6) No road crossings to worry about
Cons:
(1) Hand timed (no chips)
(2) Double out and back for marathoners
(3) Shirt - plain white, no year, looks to be cotton and not technical shirt
(4) Medal - could be more event specific