I was told at the time that the AK series are better than the MJ series - though both look similar. I have the AK-600, didn't really need a 65" laminator, but for a couple hundred bucks difference it's nice to know it will work if I ever upgrade to a larger printer.
The biggest issue with these laminators is getting the setup and roller pressure correct. Typically, I don't sled or do other traditional methods for threading mine up. I raise the rollers up about an inch high, and then feed the laminate through the back side. I then put a piece of scrap backing paper on the bottom roller and slowly adjust the top roller down JUST UNTIL the weight of the roller makes the top adjustment knobs go loose. This way, only the weight of the top roller alone (no extra pressure) is doing the work. Once I have it set up I can run a whole roll of material through mine with virtually no problems.
*FWIW - the VT series looks nice, only difference is that you have one crank to lower the top roller vs 2 independent cranks on both sides for the AK series. At times it would be nice, but I've come to terms with mine and am happy with my purchase.
**If you're a small shop, these laminators are ideal. If you're printing and laminating several rolls a day then it might be a better investment to go with the Seal or GBC, etc.