Keep in mind that this is a hostel, not a hotel and you will be quite happy. It was a great hostel, clean, well-run and roomy. We were only there one night, not even long enough to use the showers, so I can't speak to those, but the bathrooms were basic and clean. Our room was clean and the bed really comfortable. The private rooms are definitely set up for groups or families as our room had 5 beds (4 twins and one full). We definitely had plenty of space!
The price for the location near the Park can't be beat and if you want to see the volcano at night, staying nearby makes it a much nicer experience.
One surprise for us was how small the town of Volcano was and how few options for food there were. We arrived around 8 after viewing the volcano in the Park and after asking if we'd eaten, our host was quick to point us back out the door to find food which we really appreciated. There was a small market in town that closed at 8 and a few restaurants that closed at 9. We initially stopped at the closest and were a little shocked by the prices. We ended up happy though, eating at the Thai Thai restaurant nearby which was the cheapest and had amazing food!
Some guests noted a musty odor, which is true, but I think would be hard to avoid in such a wet location and I honestly would not have particularly noticed it or thought to mention it if I hadn't read about it in other reviews.
We had a great visit and I would have been happy to stay longer.