Looks good. I researched flight data suppliers & GDS companies recently for a side project and found them either very expensive (QPX falls in this category - having to pay several cents per query makes it virtually impossible to do anything creative) or lacking coverage for LCCs in Europe, which is my target market.
So naturally I'm quite impressed with Fareportal and will give it a try. I did do a quick search on CheapOair and didn't see Ryanair among the results (although they do have a flight for that route and date). I know they're icky about third parties advertising/[re]selling their flights but there's some suppliers that do carry their flight data (ie Travelfusion, which politely told me to come back once I have a working product, chicken and egg much?).
I'm not keen to book flights on behalf of users at this point since I have a (not thoroughly documented) fear that regulatory matters will make it difficult/expensive to operate an indie OTA but that's TBD.
If you are looking for API access for LCCs, check out http://www.azair.eu/
They are the best, they have availability + pricing + schedule +... data from every LCC that is out there in Europe.
I use their regular website myself for all travels within Europe when flying LCCs since they show you split ticketing options as well as do a real search when you enter lets say, from France to XXX (for all airports).
Skyscanner does promote the "take me anywhere feature" but it doesnt show you any real availability data, only displays flights other people have searched for.
I also got an email the other day from http://mystifly.com which also promotes LCC but I haven't tested them yet.
I'm happy to answer questions as I'm helping several companies switch over to Fareportal at the moment.