I own both, and I like them both. They have different uses in my personal opinion, just my opinion.
I prefer pocket carry and that is how I employ the LC9, because it is a very slim & fairly light pistol with plenty of punch.
I use the SR9c as one of my HD pistols, it is more accurate, carries 17+1 with the full-size mag. and is very nice to shoot. It has the same controls + that the LC9 has, the SR9c has the ambidextrous safety & mag. release.
If I could have only one it would be the SR9c, it's about 80% as concealable as the LC9 and gives you much greater flexibility as a personal defense weapon, however, I bought the LC9 prior to the SR9c and still prefer it for CC.