This is similar to asking someone from Sony how to go about getting their bosses to skip over Samsung for their phone purchase. Sony of course hasan answer, but if your management is even semi-aware of major 2015 industry events, they would laugh you out of his office.
The Okuma answer is not exactly an honest portrayal of Doosan Machinery support. Doosan partnered with Ellison Technologies last fall, and now Ellison is now their US Distributor. This is a huge score for Doosan as Ellison is a well established distributor with an large existing infrastructure and support network in place. Doosan previously has never had the opportunity to team with a large distributor. The partnership allows Doosan with rock solid support that at the very least equals Okuma's support structure.
As most of you are aware, Ellison historically has ranked number one in sales, service and engineering support in their regions in the US CNC industry. Ellison was up until recently partnered with Mori Seiki. Mori Seiki is Okuma's main rival for market share in the US when considering prestige, pricing, technology, etc. Okuma has similar distributors to Ellison such as Gosiger, Morris, etc. Okuma's distributors are no doubt great partners for Okuma USA. Doosan has gained an equal level of distribution and support and are absolutely 180 degrees from "uncertain". This brings a huge amount of legitimacy to the Doosan's US operations. The sole reason Mori split from Ellison was Mori Seiki DMG decided to go factory direct and eliminate using a distributor/middle man altogether. They are the first large CNC manufacturer to strike out on their own, as even Haas Automation is not totally factory direct.
That being said, Okuma makes a stellar machinery and I enjoyed operating them for years. Doosan is almost in a separate market compared to Okuma and Mori Seiki and their product pricing. Okuma/ Mori-Seiki are the BMW/ Mercedes in CNC, Doosan is closer to the Volkswagen. And just like the cars, Doosan has and will sell more CNC internationally then either of the luxury brands. But you get what you pay for with either choice. Reliable Economy. No propertiary next gen NC controls with the latest bells and whistles, just a straight Fanuc NC. Nothing wrong with that, just saying that's what you get with a mid-tier machine and mid-tier price. I bet most operators would prefer a luxury brand to work with all day, makes the job easier. But I bet most shop owners/purchasing managers would prefer the Doosan, especially if the specifications match what the shop needs. I'd prefer to drive a BMW, but my paycheck demanded VW (used and go easy on the gas pedal lol)
Regardless of you need to choose among the three CNC brands, then it comes down to what you need machined, are you doing prototypes or production, if it's a horizontal do you plan on adding APC's or Barfeeders, extended warranty periods, NC Controller preference, projected uptime, price, etc. Service and support should be very good for all three. If anything I would be most concerned about 2016 Mori support as they are busy building their in house distribution plan from the ground up. But given their legacy I wouldn't be too worried, especially long term.
Thank you to Okuma America to participate in an AMA, it demonstrates their commitment to the manufacturing industry, and I am glad they are in Charlotte always just a phone call away. Okuma makes a great product, there is no need to write deliberately misleading answers to an Okuma fan boy's cheerleading question. It's poor form to spread rumors and half truths about your competition, ask politicians. It usually does the opposite of what you intended, is very unprofessional and reflects poorly on your company. If you don't want to promote or give the competition positive words, that's fine. Just politely decline the question or defer and change the subject.