I've flown Easyjet and Ryanair.. there are a lot of ways they are similar however if the prices were the same and it was a quick choice between the two it would be Easyjet.

However for the last year or so FR has been cheaper and that is the only reason I'd fly them first.

But I am a basic flyer - I only take carry on luggage, don't buy anything except for the occasional JD (and FR don't even sell that) and tend to sleep on short flights.