Wanabee Quiltin

I have had many problems with my HQ Avante long arm since the day I bought it. I have had a repairman out three times now and this last time he repaired the timing again. He told me that he thinks all dealers should take the machine out of the box and check the timing before selling it to the customer as over half the time the timing is off. He said he believes my machine has a timing issue in the main body of the machine and he will take it apart the next time he comes to repair my machine. He is not affiliated with the dealer of my machine but works at another company. He told the owner of the store where he works that he wants to open all the boxes of the machines and check certain things to make sure the long arms work and the owner refused. The repairman said he makes calls for over half of the machines sold because of this one problem. The customers are always upset because they have started sewing and have nothing but problems and it's not their fault. I have had to pick an entire quilt apart because I didn't know what was underneath. I have learned to take an extra piece of fabric and sew on it and then use a mirror to see if my bobbin stitches are OK. Right now my machine is OK but I wonder when the timing will go out again.