<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by Happy:
Our final destination is not Osaka, but Hakata.</font>
In that case... I've taken a bus from Tokyo to Hiroshima once and it was long enough to sleep, if mostly because the bus was half-empty and I scored the back bench. Although if you didn't have the rail pass I'd be very tempted to suggest flying, eg. with ANA's Visit Japan fare you can get a one-way flight straight to Hakata for Y11000 (IIRC).
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They are deep recliner seats. according to the description, the recline can reach almost horizontal level. There is foot rest, slippers, blankets.</font>
Those look an awful lot like the Dream Bus seats, and even if the description says ''kanari suihei ni chikai kakudo ni made''
("close to fairly level angle" -- note the dual qualifiers there and the lack of the precise angle?), they are quite unlikely to approach the same planet as "full recline".
But FTers take heart -- at least the description tells passengers to watch out for the passenger behind them when reclining!
<font face="Verdana, Arial, Helvetica, sans-serif" size="2">It sounds to me Dream is better than Y seat, the Y seat you referred to probably is the cheap Young 18 buses - which has 4 seats one isle versus the regular night bus which has 3 seats 2 isles. The Young 18 costs only 5000Y one way, versus the regular Dream costs 8610Y one way. So I pretty much the Y type seat you mentioned must be the Young 18.
Edit : the total time is approx 8.5 hours between Tokyo and Osaka. They turn off light once bus departs. I dont see how you cannot get 5 hours sleep.</font>
Err, no, I meant your average airplane Y seat as a reference point -- the buses I've taken were ordinary Dreams. One major reason you cannot sleep 5 hours on a 8.5-hr trip is that the bus stops quite literally every single hour at an expressway rest area. Why, I have no idea, but it does. And in proper airline style the first hour is taken up by a safety demonstration/bus facilities video, and the last hour by morning calisthenics and a useful message informing you that you're approaching your destination.