Wins over Leinster, Cardiff Blues, Newport Gwent Dragons and Connacht see the Warriors sit joint top of the table with Ospreys.
Glasgow now head to Italy to take on Teviso before another away tie at Ulster takes them up to their first match in the European Rugby Champions Cup against Bath.
Duncan told the Evening Times:: "Treviso is a tough place to go and play. They have a good home record and always do well at home in Europe as well.
"It's quite a hostile environment and although the weather is better than Scotland their track restricts an expansive style of play.
"They have made changes over the summer so there will be a lot of new combinations. It's up to us to match that and play with confidence after our recent wins.
"Now that we've come away with four victories, it's about keeping that momentum going. Although we're not firing on all cylinders, we are learning all the time.
"The aim is to get two good wins before our big European game against Bath at Scotstoun in a few weeks time."