Now what you need to do is verify what model of guts the phone has now. Do the following to investigate:
#,*, Menu, Right Arrow
Select Unit Info
Select Phone Model
See if there is a revision next to where it says i736, usually there will be a letter beside the model number or directly under it. If the phone has been upgraded before, you will need to know the revision letter before you sent it to Moto for repairs to see if it is further down the alphabet than when you sent it in for repair.
Should you not have a revision letter, or the letter matches what you had when you sent the phone in... you have not had the guts upgraded, they just put a ground plane kit on the antenna to give it more radials. (This is explained in other posts I have made). It will give you better signal, but will not improve the bad platform the phone was built on.
Most people in here would agree the that old i730 models were horrific, but the newer i730 models seem to get the job done.