Celotex or SuperQuilt

We’re in the process of insulating a 50mm cavity wall and are considering either 75mm Celotex or SuperQuilt. Based on your experience, which material would you prefer? We know that Celotex has a better R-value, but we're curious if doubling up the SuperQuilt could achieve a similar performance. My dad is an experienced builder and prefers to retain an open cavity to prevent dampness which is why we’ve considered SuperQuilt. Cost will obviously play factor in deciding but performance and reducing the risk of damp is more important. We’re open to expert insulation advice to help us determine the best option.