I had an old PSE Deer Hunter before I bought a new bow. I upgraded all my accessories except my sight. When I bought my new bow I purchased only the sight. I see nothing wrong with upgrading accessories to expensive ones on a cheaper bow. The accessories can be transferred and as mentioned above you don't have to put all that $ out at once later on down the road.
A hunter is not a man who kills animals but, a man who holds immense knowledge, loves, respects and takes great steps in the preservation of the creatures he harvests. He is loyal, grateful, responsible and ethical in every aspect of his chase. He is who I strive every day to be.