location wise, Sukhumvit 11 is an excellent place and I know this hostel - it's in a good street. There are also a couple of good guesthouses/hotels VERY close to National Stadium BTS station, on a street called Kasemsan Soi 1. Hotel Reno has a pool (albeit small). You can check on google for more details about this hotel, and others in this street. I used to live in a condo on this street until last year (when I moved to sukhumvit, just up from Soi 11), and location-wise it's the best place I've lived in BKK.