Years ago I ran a pull push, it needed a compressor, all equipment was very expensive, even without expert advice welds were great, however a lot of trouble with wire feed. Have used the spool style, absolutly zero troubles, although bulky compared to the air powered. Tried to keep the line as straight as possible with the push pull, but if you have ever worked on an aluminum deck etc, you will soon find that aluminum duplicates a magnet with holding power, inability to slide metal tools etc on surface, those conditions duplicated in sheath, lubricants were also tried but unless serious attention i. e. strictly aluminum operater operated, casual user probably will have problems. Any weldor picking up a spool gun for the first time can just go to work, just make sure enough inert gas coverage. In a showroom saw that high priced Dodge sporty car, sporting black dust on welds on exterior not enough gas coverage. (Pride in Workmanship?) How I used to test my welds for the first time, stainless, aluminum etc. get a bucket of COLD CLEAN water, weld about one inch on the type and condition of material you will be welding on, immediately plunge into water, swirl untill hand cold and place in heavy vise and attempt to break it. In other words give it a disruction test, keep the sample, (you may need it)