I have used ESC for years, it is great. The S-50, 550, Emax and Universe of Sounds libraries I posted here (in sf2, akai program + wav format) were done with that program. Easy to use, and audio quality is the same as original. There are lots of customization options if you want to change things around.
Every old and obscure sample format, disk image, etc, that I have put in, ESC has nicely converted to modern usable files, while preserving correct loop points and other parameters.
For tweaking it has good auto looping, but sometimes you have to adjust it yourself.