If it matters Bike Radar Review gave the Giant 5 stars and the cube 4. You also need to read about pro's and con's with disk brakes.
Personally I don't think disk brakes do a dang thing after I tested my rim brake bike against a friends disk brake bike. Here's the specs on that test: the combine weight of me and my bike was 87 1/2 pounds for me and 89 pounds for him; I was using Hutchinson Intensive 23c tires and he had Conti 4000s 25c; I have AL wheels he has CF wheels with an AL brake track; we adjusted our air according to the online Michelin inflation calculator and used the same pressure gauge; and do to a You Tube test done by 2 pro riders where the one rider altered the outcome by sliding back toward the rear of his bike which made his disk bike stop faster we made the rule that we had to stay in the center of the seat and not move; we did 3 sets of 3 tests one after the other without resting between stops to test brake fade, first set was at 15 mph, the second at 22 mph, and the third at 30 mph. What we found out was that after those stops he and I was within a foot of each other during the first 2 sets, sometimes I stopped shorter and sometimes he did which we attributed that to probably reaction time differences. Was interesting was at 30 mph I stopped faster ever single time, which we think was due to the disk brakes fading because the disks was so hot I burned my finger touching it, but the rims were not that hot, but still there wasn't more then a 2 foot difference, which probably would had started to increase further if we kept doing stops like that. The other thing you must consider with disk brakes is that it cost more to maintain them, but with rim brakes you wear out the rim faster, the end cost result is the same except with the disk brakes you spent a lot more time maintaining them. Some say rims on a bike get dirty because they're closer to the road, this is pure nonsense in an effort to push disk brakes, I've ridden rim brakes for over 40 years and never had an issue with the rims getting dirty do to be close to ground. Of course the final arguement is disk brakes work better in the rain, true but only to a point, a disk brake still won't stop until the water is wiped from the rotor surface but it wipes it faster because the rotor is not as large in diameter as a rim. And here's something the pro disk people don't want you know, rim brakes are disk brakes!!! think about that, you have a pad that contacts a metal surface, both do that, the rim brake has better fade resistence because it's larger surface area dissipates heat faster which is why my test proved that at the higher speeds after 6 previous ones after the third testing I was stopping shorter.
