I have flown a r/t with Ryan air from Charleroi to Krakow on a US Passport.
I booked the ticket online without any issues and printed my boarding pass. I made two copies and placed them in different bags to avoid the chance to losing one.
At about Charleroi and Krakow the visa check line was the bag drop line. I had a short line in Charleroi, no more than 5 minutes or so and no line at all in Krakow. The process is done before you clear secuirty and takes almost no time at all. The agent glances at your passport and stamps your BP.
My overall RyanAir expereince was fine I had no complaines. Both flights were ontime and no one was rude. I knew what their baggage allowance was and planned acordingly.
Most Ryan Air fees are a tax on the disorganized, which is why I would have expected them to get higher markets here on FT.
My seat did not recline and had to listen to constant annoucements with FAs trying to sell me stuff. However, I was expecting all that and didn't want to pay three times more to fly a major.