First, both courses are excellent. Both providers are of the highest integrity, and they are successful Amazon sellers in their own right. I am an affiliate partner of each, which means I may receive compensation from the provider if you buy one.
The fundamental differences:
Coaching: If you need any additional substantial help from Jim Cockrum's Proven Wholesale Sourcing, Jim's team will suggest you hire a coach. I have heard this runs $3500 and up to start. There is nothing wrong or unethical with them doing this, and their coaching is excellent. That $297 price simply does not allow them to provide personalized help to you for free - doing that would simply put them out of business. That said, the course itself is of incredible value.
On the other hand, The Wholesale Formula gives you 6 live Q&A webinars AND a private Facebook group, where any question/problem you have is answered by the course founders themselves. That isn't one-on-one coaching but more of a 'group coaching' module. That's why the Wholesale Formula price is higher (yet still far less than, say, the $3500 you would pay for a coach from Jim Cockrum's team.)
Also, when you pay that higher price for the Wholesale Formula, you receive things you won't receive in Cockrum's Proven Wholesale Sourcing:
1.) Generous discounts to their fulfillment center partner (Prime Zero Prep). This is for when you buy from manufacturers. Instead of you receiving/inspecting/processing the units, Prime Zero Prep handles it for you and sends them to the Amazon fulfillment center, for a very reasonable fee. This is a BIG headache-remover for you.
2.) Free $3000 in useful bonuses from me. When you buy The Wholesale Formula from me (see the link here), I'll give you $3000 worth of bonuses (some of which I paid for for out of pocket) . I did this after Wholeasale Formula members said "Hey Jordan I need help with ______ for my Amazon busimness". That specific help includes $100 worth of freelance help, a $1997 package from a major, trusted fulfillment center, and a $150 Amazon product list (a list of products on Amazon that are ideal for you to consider sourcing because they meet desireable critera.) Again, all free for you. More details on those bonuses are here.
Two more subtle differences:
In short: If you're just looking for solid wholesale sourcing and selling training and you don't feel need live, personalized help, Proven Wholesale Sourcing is excellent. If you are seriously looking at making wholesale the cornerstone of your business and growing rapidly, and you want to get expert feedback and answers to your questions along the way, I highly recommend The Wholesale Formula.
See my research page for The Wholesale Formula for more in-depth discussion.