It really depends on who you're talking to, for the most part especially dealing with clients, you get better treatment wearing a suit. However you dress, you

It really depends on who you're talking to, for the most part especially dealing with clients, you get better treatment wearing a suit. However you dress, you should look good, if you're confident in t-shirts and khakis presenting to a room full of suits then do it, if you're more confident in a suit then wear a suit.