Just my opinion (and you know what they say about opinions). I was in the same situation a few months ago, trying to decide between a new Syncrowave 200 and a RED 225. I do small welding/fab on the side to help pay for school, a large job came in that required multiple, LONG welds on 1/8 to 1/4" aluminum. My only draw to the 225 was the few extra amps, but as it has been mentioned, the extremely limited duty cycle at those extra amps almost negates the benefits. About the same week I was ready to pull the trigger on a new Syncro 200 package, I found a screaming good deal on Craigslist for a 1991 Syncrowave 250 complete setup minus bottle in great condition.

I am really glad I waited/the 250 fell in my lap as it is REALLY nice to have the ability to turn the dial past the 200 mark. Remember the old saying of "you can't use amps that you didn't buy" unfortunately amps to a welder are not like minutes to a prepaid phone, you can't just add more.

Another thing to consider is that there may be extra costs associated with a new machine such as filler, torch consumables, argon bottle. I would assume that you already have those from your econotig. One other thing I would like to mention is that if you feel 3/16" and 1/4" are in you common diet shall we say. You will probably want to look into a water cooled torch to replace the air cooled (WP17 I believe) that comes with the Syncrowave 200 and the RED 225.

Don't let people scare you off the amp input requirements of the Syncrowave 250. I run mine up to 275 amps in A/C tig on a 50 amp breaker and have so far never tripped it. I did once trip it when turning the machine up to 310 amps just to see what a 310 amp tig arc felt like (ha ha ha). The key to being able to run on this lower breaker is due to the fact that my machine does NOT have the power factor correction caps in it. So when shopping for a used 250, you may want to keep that in mind.

One last thing is that I feel you may need to make a decision as to how you want to proceed with your side business. That is do you want to venture into portable work (choose the TA185) or do you want to get into larger, thicker items that are brought to you (Syncro 250)? Although the Syncro 250 may cost more than the 200 new, the extra 100 amps that you gain could really help you to expand your small business, I know it did for me. Not many "on the side" guys have a 300amp ac/dc tig at their disposal.

Just a few things to consider.