An example of strong marketing sensibilities, Not So Hostel is many great things and a few not-so. At the end of the day, it would be nice if NSH were more explicit in identifying its amenities. That said, in general, NSH is a smart idea placed well into the thick of downtown Charleston; that is, it's where you want to be (in the event that you want to be in downtown Charleston and not paying $250-plus per night). I can only speak to the private rooms in the annex location (Cannon St.), so do not take this information to speak to the conditions in the main house (Spring St.).
My wife and I reserved the Kendall room, which the NSH website describes as "a small studio apartment [with] its own private bathroom and kitchenette ... ideal for one person." I am on the taller side at 6'1", so I was expecting to feel cramped in the space; somehow, I felt perfectly comfortable. With two people in the room, as long as no one tries to make a quick move in the small walkable area, all seemed well. Best yet, the bathroom was attached to our room, and it was clean and very modern. I don't know that I've ever had a showerhead high enough up that I don't bump my head on it in the shower. The bathroom is small, mind you, but not in a claustrophobia-inducing way. On the first floor and attached to the kitchen and public space, the Kendall room was well situated, clean, and mostly comfortable.
After we unpacked our bags and made the bed with the sheets provided by NSH, we made for downtown, and it was a quick walk. Two blocks and you were on King St. Restaurants and shops everywhere you looked. However, when we returned home later in the evening around 10:30pm and got into bed, we started to notice a few issues:
1. The bed was an odd size. I've never had so much of my leg hang off a bed; even while somewhat curled up, I could barely keep my body all the way on the mattress; I couldn't tell you if it was a full or not.
2. The bed was made of a plastic material that doesn't let your body dissipate its heat (think vinyl/urine-proof plastic mattress for children); instead, you seem to hold your heat, a condition that makes getting comfortable practically impossible;
3. The sheets provided by NSH were also a heat-insulating plastic-like material that felt slick on your skin and made me wish I had packed my sleeping bag to lay out on top of it all;
4. The air conditioning wasn't working correctly in our room, either; our neighbor (J_____, who lives in the next-door unit) remarked that it was also very muggy in his room but that the thermostat was in a place that we couldn't access (sounded like it was in one of the other guestrooms); he suggested that we crack our first-floor sliding glass door to let in the fresh, cooler air from outside. However, we weren't comfortable with opening our door to the outside world and whoever could walk right into our already tight space.
We ended up trying to lie on top of the sheets and beside an oscillating countertop fan that did little more than dry out your nose. So, after two hours of tossing and turning, we called NSH and were only able to leave a voicemail. After waiting for about 30 minutes, we contacted another hotel off the peninsula who gladly provided us boarding at 2:30am and even went so far as to let us have a late checkout at 2:00pm.
All that said, I have passed nights in hostels before, and I grew up in Europe with smaller accommodations as a facet of everyday life, yet I've never had such a problem until NSH. We had a three-night stay planned with NSH and paid for the three nights at check-in. NSH has offered to reimburse the final night, which isn't really satisfactory and has forced us to ask AmEx to mediate a dispute claim for two remaining nights. We'll pay for the first night, as our stay made it impossible for anyone else to stay there; but, in the same way, we can't fathom paying for the space for two nights we could not use the space.
Incredibly enough, rather than attempt to work with us to resolve our issues and perhaps get us to stay the remaining two nights (arguably a herculean task after the first night), NSH immediately jumped to offering us a partial refund. This action makes me think that they have a procedure in place for such recurring issues. Calling yourself a hostel, though, doesn't excuse your obligations to provide your guests with satisfactory amenities nor earnestly aiming to work with guests to help make their visits memorable in a positive way.
Would I suggest Not So Hostel to friends or anyone else visiting the area? Yes, with a few caveats, but still yes. If you want to be downtown and not worry about driving, then NSH is a fair bet. Definitely get the private room; definitely bring your own sheets; and definitely find out about the working conditions of the A/C-heating (season-depending) within the 5:00pm-10:00pm check-in window so you can talk to a real, live NSH employee (i.e. not voicemail) read more