To that end: Your clothes should generally be such that they allow you to feel comfortable and fit in.
If you are in a business casual environment and REALLY feel more comfortable in a suit at work, then by all means wear very conservative suits from Brooks or Press -- just wear them almost every day so people think it's your uniform (and not an attention device). Go with white and blue shirts (easy on the Frecnh cuffs) and plain ties. Don't get anything that draws undue attention to itself. Make sure you are seen every now and again without a tie -- it will make you seem more human. (if you wear a suit everyday, 3 suits are fine for your rotation.)
If you're in a business casual environment and feel more comfortable in that dress, then by all means wear that.
The most important thing to remember is that you want to look like your work is the most important thing to you. That means wear nothing that attracts undue attention or looks like it is trying to gain attention. If you insist in wearing a suit in a business casual environment, you WILL become "the guy in the suit". But if you really do look more comfortable in a suit, and your suits/shirts/ties are not attention-grabbers, then people will just assume it's a kind of uniform for you.
This doesn't apply if you are a fixer - i.e., like Clooney in Michael Collins - then you can dress like this:
There is a book that captures the perception v. reality of overdressing at a Biglaw firm - "Double Billing." It is not part of the main plot, merely some musings on how the other associates react to a guy that dresses "too well." But beware - read that book and you may leave that big firm and never go back.