I flew Ryanair last month on a domestic flight in Portugal FAO - OPO. It was the only airline flying direct without having to waste most of the day transiting through LIS, so I took the risk. In other words, I didn't choose them for price reasons.
I paid extra on booking for 2 checked bags, 2x15 kg. I also paid extra to select a seat and get priority boarding. I had 3C. Would have preferred 2C but after I selected it during a dummy run on the booking it thereafter showed up as allocated (even though it wasn't, and was empty on the flight. I could have had 2D but it was a bulkhead and I like to have my handbag nearby, not in the overhead bin).
I remembered to print my own boarding pass and managed not to lose it all the way from Australia transiting through UK and during my few days in FAO.
At checkin I was terrified because my bags were actually 1x18kg and 1x8kg and couldn't really be repacked to distribute more evenly, but the guy didn't make a fuss about one bag being >15kg and just checked them both through.
They gave about a 20 minute window to get to the gate after they announced what gate it was. Like most European airports I went through on this trip, the gate number was not revealed until about 45 mins before scheduled departure.
"Priority boarding" meant that I got to be the second person down the stairs, on to the tarmac and waiting by the red rope to be allowed to approach the aircraft. We stood there for about 15 mins. Luckily it was a nice day as there was no shelter at all if it had rained or been blazing hot. The queue behind me appeared to be a total scrum.
On board, the first 6 or so rows had a total of 3 pax. The rest of the plane was packed. I guess the first 6 rows are reserved for those paying to select a seat. A few people tried to get themselves a bit more space after take off by moving forward but the crew sent them back to their allocated seats.
The FAs were a mix of Portuguese and Irish. The pilot was English (going by accents and languages spoken).
Almost all pax brought a wheelie bag onboard and most of them looked like they were at or over the weight limit. Even though the first 6 rows were practically empty, all the overhead bins were crammed.
During the 50 minute flight the crew came down the aisle 3 times to try to sell stuff, once more to distribute a small magazine and once at the end to collect the unwanted magazines. There was no IFE.
The flight was roughly on time and it took about 15 minutes to get the bags on arrival. About 5 pax had paid for checked bags.
Overall I would rate the experience as about 6 or 6.5 out of 10. I had been expecting an epic fail but it was actually not too bad. They will never be my preferred airline but they did their no-frills job ok and I got where I wanted to go. The main thing I didn't like was the constant feeling that if I made some kind of mistake and didn't follow their myriad rules, there would be no latitude from Ryanair for human error and I would be penalised.