There are several excellent lower limb surgeons at Hollywood Orthopaedic Group, who do ACL's, they include Colin Whitewood, Gavin Clark , Sean Williams and Clem McCormack they all do lots of ACL's and also are no gap providers. I would confidently go to any of these guys. Talk to your own GP and have a look at their website.

Obviously POSM surgeons are all excellent, however there will be a large gap for exactly the same operation. Out of the guys there I think Yens
Buelow has done most ACL'S, Holt, Annear, Hogan, Hewitt, Witherow and Greg Janes are all excellent as well.
Remember though all Surgery has it's risks so there are never guarantee's, 95% of time though there should not be a problem.