It is a frequent question that comes up from candidates interviewing 'How should I dress?". I believe you should 'Dress to Impress'. I am a firm believer that as an interviewee you are better to over dress than under.  

Oscar Wilde - 'You can never be overdressed or over educated.'

Although you do need to take into consideration the particular organisation. For example, being suited up for start up running out of a garage might not be appropriate. However, have pride in your presentation and don't be afraid to over dress. Remember you only get one first impression, so make it count.