Which one is better?

As I own the green dial Hydroconquest I am biased!!

I’m going longines all day

Both are great but you must see them in metal and try on. For me Oris wears waaaay better but I prefer the look of Longines. Oris is also a bit slimmer and comes in greater variety of sizes, colors and materials. If it was my choice, I’d pick Oris.

This is one of those toss ups where they're so close that whichever you like the most is the clear winner. No wrong answer.

I can speak on the Longines, I own that model. It’s a fantastic looking watch and the build quality is far better than expected in the price range. I own Oris but, not that model. Oris is a great brand as well.

Had an Aquis, it was superb and I very much enjoyed it. But ultimately it left the collection because I got fed up with not being able to swap the strap easily or cheaply. Great watch, not a fan of integrated bracelets (tho much prefer the Aquis integrated bracelet than anything Gentaesque)

Oris is a better watch, 5 days PR is unbeatable.

But the Oris price is double of Longines in my country, so I pick Longines.

Both are great watches. Make a list of what's important for you. Like for example;

Versatility

Wearability

Is it a strap monster

Heritage

Give each watch points in the categories and summarize.

I absolutely love the conquest series and Longines as a brand so that would be my choice.

I strongly suggest you to take a look on the Christopher Ward C60

I appreciate Oris, especially their Pilot series, but I’ve never been a huge fan of the proportions or the integrated bracelet of the Aquis.

These may be a toss-up if price is close enough.

But...the Longines will be more versatile as the Oris has an essentially integrated bracelet. So strap options will be more limited.

I have had a Hydroconquest and an Aquis for a couple of years. Both decent enough but neither of them especially great. The Hydroconquest is badly let down by the cheap clasp but keeps time well within COSC limits so on balance just about gets my vote.

Don’t be put off by the Aquis lugs, there are plenty of straimakers on Etsy who make bespoke good quality straps surprisingly cheaply.

Thank you everyone. I am finally going with Longines Hydroconquest. ❤️