I have been on 4 BF flights in the past 3 months and I have only seen or heard from the concierge once and found him completely useless. On this occasion, I had just settled into my BF seat on a CO flight from MXP-EWR and asked the FA about my wife possibly switching seats with me because she was seated in front of Y. The FA didn't think it was possible but he asked the concierge to confirm. The concierge rudely stated that we could only switch seats while the aircraft was still at the gate due to federal regulations. So, he was both rude and ignorant of CO's policy on this. I did not push the issue since they both said no. During the flight, the FAs acted as if I was bothering them whenever I asked them for anything. Upon landing in EWR, the concierge was nowhere to be found and neither was my primary suitcase. I am now sad to say that I am considering other alternatives when I have business overseas