Is the upgrade worth it?

[kyle.temple]

So, I just bought myself a used Specialized shiv tri bike. Took it to the shop, and noticed that the previous owner had installed SRAM 11spd shifters, but kept the original 10spd drivetrain.. Needless to say, it shifts, but not very happily. Is it worth it to upgrade my entire drivetrain to SRAM 11spd? Or should I just bite the bullet and get either Di2 or eTap while i'm at it? Or should I not bother messing with it instead, and just let it be?