Not GUI but a good replacement once you get used to it (and personally I think it's faster for most stuff) -> https://github.com/gdbinit/Gdbinit.
I remembered when I started *nix reversing and I had to face gdb for the first time. Hated it and +mammon original's gdbinit saved my day. These days I prefer gdb to most GUI debuggers.
Give it a try :-)