I was just looking at this one yesterday because right now our local dealer has them a 0 financing (it may be nationwide, don't know). They have several that have air threading. My serger is close to 30 yrs old and I haven't used it in such a long time but I can't afford to buy another one currently unless it was a used one and then I'd still want the air threading. Here is a website where you can compare several models; hope it helps
http://www.babylock.com/sergers/compare/?ID=BLE8W-2