I went through the Craftsman C3 line first. Batteries were Ni-Cad and lasted about 3 yrs. Li-ion was coming out and I was looking for a new line. I liked the size and versatility of the M12. I bought a few tools and was hooked. But, I still needed a good 18v line. Home Depot had comparable kits on sale on all major brands on Back Friday in '15 as they have every year since. I bought a red, yellow, and an orange kit. Took them all home, unboxed and compared them... ended up keeping the orange. The battery trickery with the yellow stuff was a no-go for me... 18v, then 20, then 60. Oh, and btw, the 18v doesn't fit the 20v without a bulky adaptor. No thanks.
About a year later, I was doing some exhaust work and couldn't get a couple of the bolts off. The Ridgid impact just didn't have the gusto. I had already cut the cord and the air line. I ended up going with the M18 fuel mid-torque and have since invested in that line also. I keep the orange stuff because I really like their off-the-wall offerings... cordless 1 gal compressor, cordless 18v/LP torpedo heater, hybrid fan, jobsite blower, etc. Some of their lights are also great. Now, if I need a new 18v, I weigh the offerings from the red & orange and go from there. The M12 fuel line is my go-to for 75% of what I do.
For anyone looking at the Milwaukee boxes- they are great. But, don't buy one now if you can wait. They always go on sale for Father's Day. I've gotten one each of the past two years; 46" upper & lower two yrs ago, and the 60" mobile work station last yr. There is usually a yellow one that comes out around that time as well. I think they are both made by the same company, as they are very similar save for the color.
