If you're looking for a place that is literally just to leave your luggage and MAYBE sleep, then Sunplaza will suffice.
We were suckered in by the low price and the tatami floors with futon bedding, but man it was not really worth it. We're glad we saved money, but when we booked a "2 person" room we expected to be able to fit 2 people in it. However, when we went to lay out the futons, the room was not wide enough to accommodate 2 futons in any configuration (we tried.) As a result, the 2 of us had to sleep on a single futon and it was murder on our backs.
The hotel is DIRECTLY NEXT TO THE TRAIN STATION so while that is great for getting around easily, it made for loud nights until the last train around midnight and being woken up before 6am. The room also smelled kind of funky and when it rained, despite having the window closed and locked, water got inside around the windowsill.
Three times during our stay, the TV in the room next to us was left on a timer and came on at 1am and had the volume cranked all the way up, forcing us to trek down and find the night-duty staff to open the door and turn it down. The walls are paper thin, and two nights in a row there were exceptionally loud guests occupying the rest of the hallway and we got less than 4hrs of sleep.
It's also in a kind of sketchy area, 5min from the 'red light district' with actual brothels. As a smaller woman, I was creeped out walking back there from the station at night, alone or with my companions