Steve Hansen's men endured a terrible RBS 6 Nations campaign last year, losing all five matches as they picked up the 'wooden spoon.'
However, they were a revelation at last winter's World Cup in Australia, where they gave New Zealand a real run for their money in the pool section, before out-scoring England by three tries to one in a heartbreaking quarter-final defeat.
England fly-half Jonny Wilkinson, yesterday ruled out of the tournament with a shoulder problem which needs surgery, feels Wales are the dark horses for the 2004 RBS 6 Nations.
And Charvis reflected: "At the end of the day, we lost both those games which was a bitter pill to swallow.
"But we have got to keep working and training hard.
"As a group if guys, we are pretty confident that we can retain a certain level of performance.
"Playing rugby is always a challenge, whether it is the World Cup or the RBS 6 Nations - there is always pressure."