Townsend joined the relegation-threatened club this week from Tottenham Hotspur.
And the winger – who grew up worshipping former Newcastle and Tottenham wide man Ginola – is confident he can repay United’s faith in him.
The 24-year-old winger will get his first chance to impress on Wednesday night when his new team travels to Goodison Park to take on Everton.
Asked if he was worth £12million, the England international said: “That’s for you lot (the journalists) to decide.
“Of course, £12m is a lot of money – I know that.
“But if I can reach my potential, and play to the ability I know I have, then I’m sure as quiciklly as people are saying it is a lot of money, they will be saying it is a bargain.
“Football, I know, has its ups and downs.
“It turns so quick. If I put in a few good performances, it will look like money well spent, and that’s what I’m solely looking to do – play as well as I can.”
Townsend – who can play on either flank – is hoping to excite fans at St James’s Park in the same way as Ginola once did.
He said: “I’ve always said he was my favourite player to watch growing up, so no pressure there!
“I have confidence in my ability, and will hopefully go out and excite the St James’s Park crowd, take plaeyrs on in the right areas – in the final third – and hopefully get a few assists for the strikers.
“I was too young to see him (Ginola) in the Newcastle team, but watched the highlights of all the great games over the years for Newcastle and many games over the years.”