Originally Posted by hokiefyd

Giant use good stuff on their bikes, and the Roam 3 is a very solid value. The drivetrain is on the lower side of middle class, but it works fine. The front derailleur is a Shimano M191, which is from the Tourney group. The rear derailleur is listed as "Acera", and is probably an M360. It uses an 8-speed Shimano Hyperglide HG31 cassette, and a Suntour triple crankset. My Trek uses an identical drivetrain, and it's smooth and very functional. Not top-of-the-mountain, but fully serviceable for this type of bike. The Roam 3 has a basic shifter/brake lever combo set on the handlebar that will work well. The disc brakes should also be fine; they're basic mechanical units.