Most mastering engineers just tell you about their gear: vintage-this, analogue-that, etc. And it’s obvious from their websites that most of them are used to working on high-budget recordings: which often don’t need much mastering anyway.
I specialise in mastering independent bands & artists, from all over the world, who need more than just “standard” mastering.
Mastering engineers typically make very small, technical changes to a mix, which you may even struggle to hear. But, in consultation with you, I’ll do whatever I can to make your mix as good as it can be. Of course, I also take care of all the small, technical hard-to-notice changes too: that’s my job !