With McLaren apparently still struggling with its works Honda power, and Renault having taken over the near-collapsed Lotus at the eleventh hour, many insiders are tipping that the teams may be on a similar level this year.
However, Magnussen says that the atmosphere in the respective camps is markedly different.
"There is a big difference," laf1.es quotes the Dane as saying.
"The first thing you notice is that the people at Renault seem happier. The atmosphere is more positive and people have faith in the team.
"When I was at McLaren, the team was down, but Renault is a team on the rise and you can notice how that affects the people."
However, he insists that while he was unceremoniously dumped by McLaren, he bears no grudge.
"I still talk to some people at McLaren," said the 23-year-old. "I have no problem with them. There are very few people at McLaren I have trouble with."
The new season gets underway in under a month's time with the Australian Grand Prix.