We just paid a few grand to have the compressor in our OTR system changed out. Fortunately the rest of the system was in great condition and seems to be holding up (knocking on wood as I type).
If it leaked out that quickly it would seem that they should have caught the leak or they did something wrong in the repair process. I'd keep pushing them to see if they can actually fix it, as I don't know of anything that will cool as well as OTR.