Buying a Miller Syncrowave, Pros, Cons and Advice?

You can't get any better for Aluminum & Stainless than a TIG, IMHO.

About 15 years ago I convinced the boss to replace the older stick welder with a TIG. We bought a Miller Syncrowave (250 I think) It had the flexibility to switch from aluminum to stainless steel to plain steel in just a few min. It allowed an average welder, like me to turn out some very professional looking welds. I have not turned it on in 5 years now. I had looked at many choices before we bought this. I still think it is the top choice as far as welder types go. If you can swing the cost, I think you will like it. Good luck.

GA to both. It sounds as though you will be welding mostly thin pieces, where TIG works well. Though faster, MIG (wire feed) is better suited to thicker pieces. There is no particular problem feeding aluminum wire, so long as the contact tube is kept clean (or replaced periodically as a consumable).

I agree in the main with the advice above - assuming this is 'craft based' work by one operator with the 'gas feel' that goes with TIG.

Miller, I regard as the top production welder, especially for thin material - they are 'stable' without peer.

However, for over say an eighth in mild steel MIG is the way to go.

MIG for aluminium is fine, but 200 amps won't do much and the wire is generally thicker, so thin material is a real balancing act of feed, speed, amps and operator skill. TIG is the better choice until around 3/16"

The best MIG aluminium wire feed solution is a handset feed motor system, which overcomes 'thicker wire' so this 'balancing act' - expensive, hence I guess your comment on cost. Also heavy over a working day.

On the 'not so expensive' side; there are Teflon liners for MIG's using welder driven wire feeds, which are basically mandatory for aluminium wire. You will have down time with Al. But, Teflon liners also have advantages with thinner steel and stainless wire over the; 'standard' MIG 'steel spring wire guide'.

So; if doing a lot, I would seriously consider the Miller TIG for thin and a 'fair quality' MIG for the mild steel.

However; you could do it all with a good quality 350 amp MIG with handset wire feed for aluminium. And if you like; a spare 'standard handset' for steel.

But; having 'horses for courses', you also save a lot of time, wire, tip and gas flush/changing, finding settings.