20.00 is a good price for any knife,give it a go.Will this be your everyday chef's knife?The only concern I would have with a 7" blade as a chefs knife is the up and down action....the shorter the blade the more efford to cut and chop,which may or may not be an issue on a long day.Also the Sontaku doesn't have as much flexability as a regualr chef knife and you might need to pick up another knife with a regualr point for some knife work,which would be frustrating for me.
I'm a bit of a knife freek and I used a 10" Henkle for years
and then as a gift I got a 10" Hattori which I would never part with,love it.Keeps an edge better than anything I've worked
A friend has a 10" Shun which I've used and I really like that as well,and would recommend either.
I've found an 8" Kershaw for 31.00 that might interest you.