I've only just recently started reading the illustrated patterns. I've always just read word-only patterns, sometimes with a pictures, sometimes without.
Usually when I'm starting a word pattern, I photocopy it and use a highlighter to mark my place. Sometimes getting lost in the sea of text can be difficult to get out of.
Illustrated patterns are a great way to crochet for visual learners though... It kind of makes you think differently.
I think it's all up to personal preference. If you do one and love it, give the other a try. You never know