We have stayed at Casa 69 twice in the last two years, and it has remained a consistently good hotel. The shared spaces feel homey and comfortable, and are a nice way to interact with fellow travelers. The rooms are clean and nice. Each are decorated differently - a bit 80s at times, but who doesn't love the 80s? They're clean and comfortable, which is what matters most to me.
Some rooms are quite loud. However, you are staying in a city center - it's going to to be loud almost everywhere. Buy some earplugs! I don't travel anywhere without them. That said, we were in room 5, in the main house and it was quiet (except for the train).
This hotel is in a great location to explore downtown San Jose. It really is in walking distance to almost everything. It is not near the airport. A taxi to/from the airport should cost around $25. I go to San Jose a lot, and if I am simply going to the airport early the next morning, I don't stay here. I stay in Alajuela and get more sleep!More