AYRMAN. Ryanair have set speed limits for all phases of taxying. If you do actually see a particular aircraft taxying dangerously you should contact the company. If your claims are correct they would deal with the crew concerned imediatley. However, as all ryanair aircraft are fitted with monitoring equipment that check and report directly to the company if the crew exceed certain parimiters, I think you may be wrong.
Maybe they should paint "HOW'S MY TAXIING?, CALL 0800-266-266" on the side of their aircraft?