I have both the ct761 and the m12. They're both great but the SO is damn powerful for how small it is. Also I ADORE the trigger. Great control and will make you wish every drill/impact had a rocker trigger. Its not meant for it but I've used it on lugs plenty of times with no issues. Its close to 160 ft/lbs. Which isn't the best out there but for the side there's no comparison. I'm a huge Milwaukee fanboy but I bought the snap on before I got into the m18/m12 line. I have a couple of the 14.4v SO tools and they're all great and all worth the money. The 18V stuff is **** in my opinion. They're ok tools but soooo expensive and not worth it and there's much better options with higher quality for lower price.
The 14.4v sander polisher is awesome, and the cordless ratchets are the best I've found, better than the current n12 offerings.
I guess it depends on what other tools you want eventually or if you're ok with buying into 2 different battery systems. If you just want a compact impact for medium to light stuff and maybe a ratchet, drill, or some lighting options then the SO is great. If you think you'd eventually like to get some saws, grease guns, multitool, etc then m12 may be the path to go. M12 is affordable as well but the 14.4v SO isn't terribly overpriced and it's built very solidly. Good luck, hope this helps.
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