why do you want to convince him in the first place instead of trying to understand his requirements, present both tools and their approach to those requirements and finally let your client decide?
We exactly had the same situation and we ended up trying both products. Some people liked Sense better than View because of the robust visualizations, no final conclusion yet. However, I would let them try both and IMO that could be the best approach. Sometimes, it is difficult to understand the requirements at the beginning since it is an iterative process.
