I got a road bike about 2 years ago, IMO mountain biking in great scenery is usually a better day out but going downhill at 50 mph is still a huge buzz 😀
At that price and above, most companies make a more ‘race orientated bike’ (Although still nowhere near as racey as a pro bike) and a more comfortable ‘sportive’ orientated bike. The difference being in the frame geometries. So for example Cannondale do the Caad 8 (race) and the Synapse (comfort).
Cannondale arguably still have some of the best (if not the best) alumminium frames. They hold their value very well too. (Check out the old Caad 9 frames on ebay, they still fetch high prices compared to competition). I think their geometry is spot on too. That’d be my choice although if you don’t mind having the Ford Focus of the bike world and want good value parts and frame for the price then a Boardman is good but they are a bit… boring.
Other are fine, nothing wrong with Giant – good for the money. Merida are a huge company but strangely not that well known over here, they actually make Specialized frames(!) Don’t bother with Whyte, Saracen or Charge.