Welding and Metalworking - Wire welding with aluminum

I have had a Hobart 135 wire welder for years. Great for light stuff and light fabricating. I been thinking of adding the capability of aluminum welding to that machine. I currently use C25 gas for steel welding and to go to aluminum I would have to get a tank of Argon and a roll of the wire. My question is? Have any of you use these welders for aluminum welding and what should I change or do differently then doing steel?

I have a similar Miller welder at home and bought an inexpensive aluminum kit that was mainly just a plastic liner and new roller.
It did not work that well in that any time there was any pressure against the wire when welding, the softness in the wire would cause it to bind and fill up my machine with wire.
I returned the kit.

If you can afford it a spool gun would be the way to go but it would still not work as well as a TIG unit.
The one below is for the 210 model and sells for $500.00.
We have a 250 Miller mig at work with an aluminum spool gun and it works ok, just takes a lot of practice to get it set up and welding right.............Not as easy as welding steel.

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Thanks GregH for your response. I was told it was a problem by a welding shop. They said they experimented and found that with smaller machines that keeping the nozzle straight along with cables with the machine with no tight curves helped a lot but they also said it didn't completely stop the problem. The also mentioned slowing the speed down help some also.
I may just give up the idea. I dont really have that many aluminum projects anyway.

Thanks again..