That's the character of Piaggio designed engine..

All Vespa has that.. also Recently just did test ride the SR GT Aprilia, also Vibrates while idling, maybe due to that Italians put stop start feature during idling.

Good,

1. More powerful than average 150cc class scooter. Especially on acceleration.
2. Compact size.
3. Awesome brakes both front and rear.
4. Bright headlight and tail light.
5. Strong support from the Distributorship (Motoplex)
6. Pirelli dual purpose tires for scooter (good grip) as standard.

Bad,

1. Bad rear suspension, too soft even at the hardest level (don't try to pillion anyone with more than 50kg of weight at the back)
2. EXPENSIVE for a 170cc scooter
3. Vibration during idle, but they have stop start engine system.
4. You can get a faster, or bigger scooter with less money, it just minus the Continental branding.
5. Slight expensive  on maintenance compare to the Asian counterparts.

My advice, if 120km I assume you need to go through some Highway? then with the 20k take a 250cc scooter, either XMAX, or those WMoto/Modenas models.

They did come with Racing Boy parts, especially the rear absorber, make the SR GT firmer but harsher on the Malaysia road.