I currently have a Trek 520 touring for my commuter (and main ride usually). It came with drop handlebars and bar end shifters.
I really don't like the bar end shifters and want to switch it to trekking bars. I'll probably just get some simple trekking bars like these:
The bike has a 9-sprocket cassette in back and 3 in front.
What kind of shifters would you suggest for the new handlebars?