I think it was easier to deal with the individual companies before the mergers were created. Heck, it might have even been better to take the stronger of the two pre-merger entities and use their name for the final company name, for example, "Hitachi". The name change as well as the merger I think tended to muddle the product lines and brand recognition.
Renesas products are wonderful. This is true for many other Japanese vendors. But they do not have sound product marketing strategy outside Japan. It is very difficult to get samples and quotation to purchase their parts. They should align with appropriate American marketing agent to gain back their lost ground.