Need recommendation for connecting to public Wi-Fi hot spots

My new notebook with Wi-Fi hardware/software arrives soon, so I am wondering
which wireless company do you recommend for use with public hot spots.

A random search indicates the closest Starbucks allows you to use iPass or
T-Mobile.

It appears the former may be free and the latter (T-Mobile) could cost as
much as $30/month. Say what?

Which of these providers do you prefer? Or do I need more than one provider
so I can use a broader range of hot spots when I travel?

Michael