I've owned the larger AK-600 (65") for almost 3 years now. On the AK series, the machine has independent knobs on each side to lower the top roller. When you web it up, you have to be vigilant when you lower the roller that you are doing it evenly. Otherwise you might see some tracking issues after you run a few feet. I typically get mine within about 1/4" and then adjust each side down about 1/2 turn each until the knobs go slack. At that point the you want the weight of the roller itself as the only pressure on the laminate. Do not try to tighten or apply more pressure by turning the knobs - just lower until both sides go slack. If you do it right, both should go slack about the same time (within a turn or two of each other).
I've gotten very confident with mine and can run anything from a small piece to a full wrap. Again, very happy with mine, for the money it can't be beat.
*BTW - I would opt for the AK-600 if I were you. For only another $100-$200 I think? It's well worth it and you never know when you might need the extra width.