After disappointment in the 2008–09 Conference play-off semi-final, Midson left Histon after firm interest from Oxford United. He joined Oxford on 16 May 2009 on a two-year professional contract. Midson featured regularly as Oxford gained promotion to the Football League after four years in the Conference Premier, and started in the 2009–10 Conference play-off final at Wembley Stadium.

On 5 November 2010, he joined Southend United on a brief loan. Following his return to Oxford, Midson scored his first career hat-trick against Torquay United on 3 January 2011. Midson joined Barnet on loan in March 2011, making his debut by coming off the bench in a 1–0 defeat at Aldershot Town.

In June 2011, Midson signed for AFC Wimbledon. On 9 July 2011, he made his debut in a 2–0 pre-season friendly win against a Fulham XI. He scored his first goals for AFC Wimbledon three days later, a brace in a 5–1 away friendly victory against Staines Town. He made his competitive debut in AFC Wimbledon’s Football League debut, a 3–2 home defeat to Bristol Rovers. He finished the 2011–12 season as AFC Wimbledon’s top scorer with 20 goals in all competitions. He also finished the season as joint-top scorer in League Two with 18 league goals in total. In June 2012, AFC Wimbledon rejected a six-figure bid for Midson from Rotherham United, and he signed an improved contract with The Dons later that month. On 2 December 2012, Midson scored for AFC Wimbledon in their first ever meeting with Milton Keynes Dons. AFC Wimbledon went on to lose the match 2–1 however. After a rather inconsistent goal scoring start to the 2012–13 League Two season, Midson hit consistent goal scoring form towards the end of the season to help lift AFC Wimbledon away from the League Two relegation zone. He passed the double figure mark for the second season in a row after scoring the only goal with a superb chip in a vital relegation 6 pointer against Aldershot Town on 16 March 2013. He then scored the winner in a 2–1 victory over Fleetwood Town which meant that AFC Wimbledon avoided relegation on the last day of the season. Midson finished his second season with AFC Wimbledon once again as the club’s top scorer, having scored 15 goals in all competitions and 13 in the league to help The Dons avoid relegation from the football league and secure a third successive season in League Two.

Midson signed for Eastleigh in May 2014 after being released from AFC Wimbledon. He was released at the end of the 2015–16 season.

In May 2017, Midson was signed for Leatherhead by manager Sammy Moore, a former team-mate at AFC Wimbledon, to take up a player-assistant manager role at Leatherhead.

On 2 May 2018, Midson was appointed assistant manager alongside Sammy Moore at National League South club Concord Rangers. At the end of the 2018–19 season, Midson left Concord, following Moore’s departure, after the club were denied entry to the play-offs due to ground grading issues.

In May 2019, Midson joined Moore as player-assistant manager at Hemel Hempstead Town. On 20 May 2020, Midson parted company with Hemel Hempstead Town following a year at the club.