The England winger had a choice of the two clubs after Middlesbrough accepted bids from both teams, and the 25-year-old opted to join high-flying City.
Despite his move not working out at the Etihad Stadium, he still feels he made the right choice at the time.
|JOHNSON PLUCKS SWANS
|12/1||Adam Johnson is 12/1 with Paddy Power to score the first goal in Sunderland's clash with Swansea on Saturday|
He told reporters: "I had the choice of going to Sunderland or City, and I probably made the right decision with the medals and the experience I have had.
"Looking back, I would probably do it again - I suppose any young lad would in my situation then.
"But it's worked out now that I am here."
Johnson feels his first-team opportunities were restricted at City by boss Roberto Mancini, but admits he enjoyed the success of winning trophies, in particular the Premier League triumph last season.
He said: "You can always look back and think. It was a slightly disappointing end, but I won the Premier League, FA Cup and the Community Shield and played in the Champions League, so it wasn't all bad.
"But it was a little bit disappointing I didn't play as much as I was capable of.
"I owed it to myself to go and play football again and enjoy playing."