I think Allen is better suited for the long haul than Mahomes. Josh Allen is becoming one of the best QBs with presnap reads which i think will prolong his career. Thats why Brady and Manning played at such a high level at such a high age. Eventually Allens/Mahomes athleticism and arm talent will decrease. And the most underrated part of Josh Allens game is his knowledge and ability to read a defense and switch to the correct play and proper blocking.