I have been on the 530 G with sensor 1 week. Gave my dex away to a friend. There is considerable learning curve, but I believe I will be happy to have both in one device. ( always lost my sensor) I particularly like the Low and High predictor. Can set alert 15-30 minutes before hitting targets. The thresh suspend goes off at 60, but there is option to continue all functions.The sensor does need a good hour to remedy a bad reading unlike the dex that adjusts right away. So far...so good.
It is only officially approved to use the abdomen. But many of us used our thighs for the sof sensor. I currently have my Enlite inserted in my thigh, because that is where the sof sensors worked the best for me.
If you use a site besides the abdomen you forfeit the right to call MM support.