Recommendations on getting a porcelain tub reglazed?

Like the title says, I’ve got a porcelain tub, unknown how old, but the bottom is kind of rough to the touch and I’m wondering if reglazing is effective and who might be good to do it? I’ve found a couple of companies in the area by searching online but would love to hear if people have had any personal experiences.

EDIT: here are some photos for reference