I've been travelling in Latin America (Central & South America) for over a year and regularly use Hostelworld to make my bookings. Prices seem to the same as if you go directly to the hostel but many hostels do not offer online bookings themselves, so Hostelworld gives you that ability.
In general, Hostelworld offers a number of options per destination but every so often there are very limited options. I expect this is simply a matter of whether then hostels have joined HW or not, but it does mean that you cannot always rely on HW.
Also, for some reason, the full range of room/bed options offered by the hostel is not always presented on HW. I do not know if that is the choice of the hostel in what they want to offer online or a bug with HW.
Connect with Facebook to get one click access to Trustpilot. It's easier.Sign up with Facebook