I've been scouting Trivago for hotel rooms for an upcoming trip. I'm familiar with the big names expedia, priceline etc. But I see good deals from websites like Agoda, Zenhotels and Splittytravel.com which I'm not familiar with. Are these websites legit? I'm worried because I've heard horror stories of people paying upfront and then learning that they didn't have a room booked on showing up at the hotel. TIA!