Over the years I've used both.If you want a good SI look into these-
http://www.cdkayak.com/products/temp...6157645b970b0d
WS has some nice ones of both types but their Pungo's all have larger cockpits than the Kestrels which can get you into trouble.That said I had the 140 and loved it.For SOT'S have a look at RTM-
http://www.rtmkayaks.com
Good luck!