Echoing the above, +1 and I recently took the Yufuin no Mori #3 from Hakata to Beppu. We travelled on 8 January which was the last day of the Coming of Age Day holiday weekend. Tickets sold out within minutes of the 30 day window opening. I agree that the trainset itself is cool but the ride and experience was a bit of a letdown.



We were in the third car, sitting on the right side. The overhead racks are pretty small, only enough to hold a backpack or small duffle. There wasn't any power available at the seats either. I've never traveled on a DMU train before where there are diesel engines in the car and not pulled by a locomotive; there was a bit of engine noise pulling out of stations and now and then between periods of coasting. We didn't bother ordering the special ekiben and relied on the many choices available at Hakata. The train was full of passengers heading to Yufuin with a very few people getting on/off at the stations along the way. Early on, there was a lot of traffic in the aisles as people went to collect their ekiben and drinks and with others wanting to see the rest of the train and snap photos.

After Yufuin, about 1/4 of the passengers rode on with us to Beppu; it was much more relaxing to have a quieter and less congested train ride and I walked the length of the train to check out the other cars and enjoyed the view over the engineer's shoulder.



I found about 2/3 of the trip to be pretty bland, scenery-wise. Leaving Fukuoka, we passed through mostly residential and industrial areas with stocky and squat concrete buildings. The rural sections were mostly farmed fields. At a few stations and crossings, people would stop and wave at us as we passed by. It got more interesting around the middle of the trip as we started intersecting sections of the Kusu River now and then. We did have a great view of the Jion no Taki Falls from our seats and the train paused briefly so we could all take pictures. Most of the announcements were in Japanese, supplemented by some short English recordings at a few key points of interest. For some of the lesser points, cabin staff walked by holding large cards with short blubs ("We are now passing the Minou Mountains..." in several languages.



From Yufuin to Oita, the scenery was mostly woods and forest, with quite a few short tunnels. I liked this stretch the best, followed by the run up the coast of Beppu Bay to the Beppu Station.

Overall, I am glad we had the experience but wouldn't be eager to do it again. We rode back to Hakata on the regular Sonic train via Kitakyushu and enjoyed the level of comfort, uncrowded cars, and en route scenery.