Here is the email I sent to Gemma from Sixt but I did not receive a reply after a week (it's possible she did not get the email or I didn't get the reply). I'm also still waiting for a copy of my completed rental agreement to understand what I was charged for despite requesting it online. The letter speaks for itself.

Hi Gemma,

I am writing to you as I post on the flyertalk website and saw that you respond to members questions about Sixt rentals. I have a complaint about a recent rental in Italy and I wanted to write to you directly to give you a chance to respond, before posting my experience online.

Our rental agreement number was XXX picked up in San Remo on 17/9/11.

We signed the rental agreement around mid-day but left the car in place during the afternoon and only started driving it around 7pm. Immediately on driving it there was an odd noise which we initially thought might have been something with that car model (Fiat Punto) but as we entered the freeway and drove at a faster speed was obviously a problem and so we pulled off to take a look. The plastic housing around the wheel well of the front left tire had come loose and was entangled in the front left wheel. We called the Sixt emergency number and got an answering service who said they could not help us directly but would pass on the message to Sixt's service provider and they would call us back. We were upset that there was not a number to call directly as we were stopped on a freeway pull out and it was starting to get dark. We told this to the operator and asked her to help but after we asked a couple of times she ended the call. After receiving no call back we had to remove the plastic housing by cutting it away from the wheel while leaning under the car. If we did not do this at that time, we would have lost daylight and been stuck on the freeway pull out until we heard from the service provider. We waited longer to hear back but received no call (and in fact they never called us). We had no choice but to drive the car, despite being concerned that the tire might be damaged as the plastic had contained some metal screws which could have been caught in parts of the tire we could not see. We drove to our hotel in Genova at around 90km/hr (not fun on an Italian motorway) to reduce the risk of a blowout and give us a chance to better manage the car in case the tire did lose pressure.

We were staying at the Sheraton Genoa Airport, so we parked the car overnight then went to the Sixt counter at the airport in the morning to explain what happened. The Sixt counter person initially told us that he was sure the car would be ok and we should continue to drive it, and in any case, there were no replacements. I pressed him and he agreed to examine the car and I handed him the plastic pieces that had fallen off the car or that we had to cut away. I was adamant that it was not safe to drive this car until the tire had been removed and examined for damage. He did not agree and made a quick physical inspection of the tire before declaring the vehicle safe, saying that this happened all the time and there was no problem. When I complained about the lack of response from the emergency call center, I pressed him to call the center directly while I waited to test their service. He did but was put on hold for five minutes and got impatient and hung up before he even had a chance to talk to an operator. He explained that the service is bad but that all rental companies are similar. I asked him for a replacement car and he said come back in an hour and he would see what he could do.

I came back in an hour and he did offer a replacement car, but at this point we decided to end the rental agreement on the basis that Sixt does not provide an adequate service. I said I would rent from Avis and then did so. He said Avis has a similarly bad roadside assistance service. I said, "Well, with Sixt I know your roadside assistance doesn't work, at least with Avis theirs might work". I have two main complaints:
(i) Your staff member returned a car to service in an unsafe state (Fiat Punto Evo EJ952DA) and would not perform a proper safety check on the car even when asked. We would suggest you check to see if this car has been repaired.
(ii) Your Sixt Assistance service operated by ACI Global did not work, either for us, or when we asked your Sixt agent to try calling it, leaving us in a difficult situation and forcing us to try to self repair and then to drive a vehicle in a less than safe state. When pressed your staff confirmed that the service is inadequate, meaning that your company is aware that it does not work, and yet you leave your renters relying on this service.

A good price, convenience etc... are all very important, but the number one consideration for renters and for you as a rental company should be vehicle safety. From our experience in Italy, safety was not a priority in your operations, even when pushed. We will not rent from Sixt in Italy again and I want to ask if your assistance service is directly provided or better in other European countries, otherwise we won't rent from Sixt on future trips to Europe either.

We were charged about $200 and have not been able to get a copy of the basis for the charge online via your website. I think it would be reasonable to charge us for one day's rental at a pro rata daily rate, but to refund any additional early drop off fees or one-way fees given the circumstances. I tried to find out what the charges would be at the drop off time but the Sixt agent said Rome would work it out.

I look forward to hearing from you.

Thanks

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