Willis has been delighted with the recognition the Dragons quartet have received, in particular Dan Lydiate who started three of Wales' four games.
Now after putting Munster to the sword last Friday, Willis is hoping the returning stars can give the Dragons to perfect boost ahead of taking on Ulster.
"To have them all back this week will really give us a lift," said Willis. "It's all very positive, especially Dan's success, and with Aled Brew, Will Harries and Toby Faletau they have all really proved themselves.
"It shows that if you perform regularly you will be recognised and play for Wales. And there are others with the Dragons who will be in the selectors' minds if they perform consistently.
"Munster was a very good win, now the challenge is to maintain that form. We gave ourselves a pat on the back on Monday, but now we will sort things out and continue to work hard.
"Performing away has been hard for us, some players are more consistent at home rather than the pressure cooker atmosphere there is away.
"We got off to a rough start this season, so we need too put some continuity together, though the Munster win bumped us up the table a few places.
"Ulster are rejuvenated by some new additions to their squad and we know how hard it is to win there normally, never mind when they are doing well.
"But we know what to do because we drew there last year and we won there the year before."