The Design Hostel was a great stay in Split! I haven't stayed at a hostel in many years and we found the staff to be very friendly and the room/common areas to be clean. There is a large supermarket next door where we picked up snacks, breakfast, and coffees.
It's a bit further out of the central area of Split than I originally thought, however it's conveniently located to a major bus route and we easily navigated the city via transit. If we ever find ourselves in Split again, I would stay here.