Works, but very expensive
Works, but very expensive compared to booking from the railway company. We ended up paying 1500 Kč (66 USD) for two 1st class tickets from Prague to Plzn. We then received the tickets, and the price for these tickets are 570 Kč (25 USD). Checked it when we found the national railway company's site, and yes: We paid almost 3 times the price through Rail Ninja. This is due to a service fee + what I reckon is a very bad exchange rate in Rail Ninja's favor (we paid in USD). So 930 Kč for nothing. These were flex tickets, but as our trip was less than 24 hours away it wasn't possible to cancel. We booked the return tickets through the railway company (české dráhy), and it was not only much cheaper, but also s more user friendly experience. To sum it up: We got the tickets through Rail Ninja, but we do not recommend it.