The tip of the Bamboo Stylus is much firmer and hence you do not need to exert a lot of pressure in order to draw a stroke on the iPad, also the Bamboo Stylus is much heavily and hence it felt more natural in the hands than the Power Support Smart Pen which is very light.
The Verge has an article entitled, The best stylus for iPad: we review the hits and misses, and the Bamboo Stylus received the 2nd highest ratings after Applydea Maglus.
Wacom Bamboo Stylus – Box Front
Wacom Bamboo Stylus – Box Back
Wacom Bamboo Stylus – Box Content
Wacom Bamboo Stylus
Sensu Artist Brush & Stylus, Power Support Smart Pen, Wacom Bamboo Stylus
Drawn With Paper by FiftyThree