I think "deep research" is a misnomer, possibly deliberate. Research assumes the ability to determine quality, freshness, and veracity of the sources directly from their contents. It also quite often requires that you identify where the authors screwed up, lied, chose deliberately bad baselines, and omitted results in order to make their work "more impactful". You'd need AGI to do that. This is merely search - it will search for sources, summarize them for you, and write a report, but you then have to go in and _verify it's not bullshit_, which can take quite a bit of time and effort, if you care about the quality of the final result, which for big ticket questions you almost always do.