I don't think that Arsenal will be able to hold on to their performance until the end of the season because they don't have that much squad depth. Manchester City really lacked a lethal striker for the last few seasons after Sergio Aguero left. But now as they have bought Erling Haaland, they will really try to push for the Champions League title which they have been wanting to win for the first seasons but were unable to do so.
So far Haaland has shown what he is capable of as he scored 10 goals in only 6 matches. So far Chelsea and Liverpool have been playing their game this season so Manchester City might have a really good opportunity to grab this and be the best team in England and possibly Europe.
Inconsistent performance have been usually faced by Arsenal not in this season but also almost every season Arsenal can't hold the best performance until the end of this season. But have advantage with Arsenal start on Primer League because last six games have 5 won and 1 loss, settle first standing position is great achievement by Arsenal in this season.
Manchester City have found and settle best striker in this season after Erling Haaland make Pep Guardiola sastified with his performance and success lead top scorer standing position awhile with 10 goals contribution in last six games. Not only success lead goals in domestic league but also Erling Haaland keep consistent scoring last two goals on UEFA Champion League against with Sevilla on first match.