I have a couple of clients who are determined to have justified text while another hates it.  I am just wondering what you guys prefer.

Its a matter of personal taste and application. You can read http://webstyleguide.com/type/align.html but imo there is no right or wrong method.

If you are adding content to suit a page then justified looks good, like on page where the visitor is not going to read it. Visual appearance is enhanced by justified text.
In case it is anarticle that is to be read by visitor, you should go for right aligned text as it is more suitable to reading. The user will find a right aligned text better to read than a justified one.
This is something that I read somewhere on net and practice from then... but as a user I find it quite right too.

I ilke justified but there needs to a reasonable padding so the the text is not too hard up against the edge. playing with ti=his might apease both clients