no experience with Icon but the folks at Clayton have been awesome at answering questions here, via email, and phone. Hopefully will be running the 2.5" Overland+ in the next couple of/few weeks.
I was also debating between these two back to the days. I went with Clayton in the end. They both have good customer service as I emailed them both many times before I made my purchase. I have the Clayton 3.5 overland plus and its been awesome for two years! And I live in Alberta Canada here and over winter conditions was no joke.