My son needs to run a 2 x 9 on his 2010 Dragon 29er. (the Canary Yellow one) He is currently running a 1x9. We prefer the Shimano stuff but aren't married to it. We are looking for the bigger top speed end and maybe a slightly smaller low end. Races later in the season will probably not be as boat race oriented. Any suggestions about a front shifter, derailleur and chain ring set-up?