I have a Galaxy S6. I don't like how Verizon is allowed to load it up with a bunch of virtually irremovable bloatware (pre-loading bloatware on an OS is something that can be found on many devices, but you're typically able to uninstall whatever you want) and the fact they lock down the bootloader. More of a carrier problem than anything so don't be discouraged if you're looking to buy one, it's a really fantastic phone save for the software.
Come to think of it, I switched over from an iPhone expecting to have a little more freedom over the OS, and while actual file system access and an open app distribution platform is great, I was hoping to at least have root privileges but nothing has been done for months so far. Again, it's Verizon's fault.
A while ago a friend gave me his LG G2 to unbrick and as soon as I had cyanogenmod running on it, the performance (response time, task execution speed and GUI "smoothness") was actually superb compared to my S6 without any mods. Samsung can build a great phone but the fact they allow carriers to bloat it to stuff completely devalues the actual advantage.
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