which is better a sram 11 speed or shimano 10 speed FD with shimano 105 11speed groupset I have bought an 11 speed shimano 105 groupset, unfortunately the 11 speed FD does not fit my bike (It is an Airnimal Chamelion).  Therefore I have a choice of Sram 11 speed FD or Shimano 105 10speed ?

please advise which is best?
Unfortunately, you should be using a 11 speed Shimano road FD with a 11 speed road Shimano shifter. SRAM will have cable pull issues. 

According to Zinn, "a Shimano 11-speed shifter will not work well with a 10-speed front derailleur because the 11-speed shifter is designed to actuate the longer lever arm of Shimano 11-speed front derailleurs." so that cuts out the old days where you didn't have to match the front shifter speeds with the front derailleur. 

So, you need to find the right Shimano 11 speed front derailleur for your frame (you're looking for "Shimano 105 5800 Braze-On Front Derailleur" (Shimano FD-5800-L) since the Airnimal Chameleon seems to have a Braze On FD).