My custom-built C8 was built as an indoor gun with an S90 spring. It shoots 310 fps with 0.2. I've played with it outdoors many times. The hopup is amazing and it gets absolutely stupid long range and amazing accuracy. I prefer use my longer outdoors guns for outdoors and usually only bring my C8 as a backup, but like Eeyore, I've never felt disadvantaged when I've had to use it outdoors.