Having watched both Vokes and Wood play many times now, I can safely say that Wood is a much better player. He is far more mobile; stronger, taller, quicker, better stamina and even has a better first touch believe it or not.. Vokes looked exhausted after 60 minutes v Palace whereas Wood still looked fresh and agile, despite putting in similar workloads. Wood is also a better finisher than Vokes.. clearly Sean Dyche sees Wood as an upgrade to Vokes as well, otherwise he wouldn't have shelled out a club record signing to get Wood.
Obviously Wood has a long way to go, but he is still young and his best years and full potential are yet to be realised.