75C for the Vaillant.  This is principally a function of the refrigerant and most if not all R290 heat pumps will do 70-75.  You wouldn't want to operate at this temperature though other than for the legionella cycle.  Vaillant at least now do this by the heat pump rather than invoking the immersion heater which is the practice with lower temperature models.

Pros:

Compact

Excellent and very flexible controller, much more so than Samsung appears to offer.  Definitely no need for external controls

Very quiet in normal operation.

App is pretty reasonable (needs the WiFi add on) but not as informative as melcloud.

Excellent tech support

Widespread service network.

Cons

Compressor makes a quite distinct buzz during defrost recovery and occasionally at other times when working particularly hard.  This can be suppressed by operating in nr mode however that compromises output so practical only eg overnight or if you have a well oversized unit.

Top surface is, in common with most ashps, perfectly flat and level thus does not shed water (why on earth?)

Summary: 

Potentially near perfect, but let down by the compressor buzz.

On balance I don't regret the choice ( my choice came down to Vaillant,  Samsung, Daikin), but of course have no experience of the others.

I can't comment on the Samsung other than to say that their pre sales tech support is literally non existent.

Hope that helps.