I use BRU too, in general. It's my favorite. But I like Flash Renamer's presets and "preset manager", and its "Visual Assist" feature (allows you to quickly copy selections in the right fields, etc.). I also like its "Free Select tool". I find the interface clear and well thought for fast changes.
I use BRU for more complex simultaneous changes on file names. If you use BRU, it's certainly not essential...