Honestly, for a non-professional (someone like me) either choice will be good and will look same in 99% of shots. So it's up to you what you consider more convenient to use small 16-50 and put another lens when you need longer reach (55-210) or just have one lens 18-200 but carry it all the time (a little bigger and heavier).
I would go for 55-210 and save money, plus I'll have an option to go compact when I need just 16-50 (which is most of time I suppose).