For smaller orders that don't warrant direct vendor price bidding, resellers can go to the bid desk of their distributor for prices. Each procurement is a custom bid. Pricing is now a function of the sales group, not the product managers. Vendors don't have much leeway in their pricing, however. All are working off the same basic costs for a particular configuration.
Price differentials relate more to brand and service commitments than to system features.
With those assurances in place, Boeing could then lock in the considerable savings from going single-source. Bid pricing will become much more automatic. When we get to that point, I would expect to see a lot more single-source purchasing. And the PC vendors will be much more tied to the fortunes of their clients than they are now. Frankly, I don't know.