The LC-1 will everything the LM-1 will do and it has an additional anolog output. There's no display on the LC-1 (which explains the extra output) so if you want to view your AFR i real time then you'll need to also install an AFR gauge and wire it up the meter. They came out with the LC-1 for all of the folks that complained about the bulk of the LM-1 unit. Yay for them but I think it would have been easier to just reduce the size of the LM-1 and get rid of all the wasted space inside the case. Anyway, they're nice units, self calibrating, and just as accurate (if not more) as the LM-1.
I was just curious about the capabilities of the LC-1. I have a laptop, and a A/F gauge that I need to hook up so I am looking at my options without spending big $$$$$
Since you're already got both of those things, my opinion would be that the LC-1 would be a good choice for you. It will feed that AFR gauge you've got there and make it ACCURATE!