The fork on the Giant Roam 3 has a hydraulic lockout vs the no lockout on the Verve, so there will be times when you are stuck with the efficiency sapping nature of a non-locked out fork on the Verve, when you would like to be able to lock it out. Also the fork is clearly a lower model from the Suntour range, than the fork on the Roam 3.

With the Trek DS 8.1, the front derailleur & rear derailleur are one step below in Shimano's component range, than the components found on both the Verve & Roam 3.