There are tons of choices for a shower floor that are not either of those. Have you looked at the Daltile Keystones line? Those have been made for 75 years and are a perennial favorite. https://www.daltile.com/products/Mosaic/Keystones

Kohler still makes two sizes of cast iron pans--if we'd been able to fit the smaller one, that's what I would have chosen. They are white, but I don't think would stain too easily. I think it's 48" x 36" (and big one might be 30" x 60"?) There are also some costlier options like soapstone or Swanstone but most of what's out there is acrylic--we didn't find too many other options. (We ultimately went with tile.)

Thank you - DeWayne, I looked over the site you linked - it looks like tile as well. Is it a special tile that doesn’t require grout? Confused as to how it’s a different option.

Everything requires grout. Like the penny tiles you are considering. A modern high performance grout has zero issues.

An acrylic or cast iron pan doesn't require grout--pretty sure that's what OP is asking about. Options for plain shower pans that are not tiled but also not acrylic or prone to staining. There are some, but not a lot.

Look at the Kohler cast iron shower bases.

They have just what you are looking for - very solid, enamel over cast iron. Not going to stain.

They include options like a built in seat (acrylic version only) and a covered drain. Sizes to fit a tub replacement.

Thank you!!!!!

An upscale hotel I was staying in had them. I was impressed with the way they looked with the drain cover. I was also impressed with how durable they were. There was no flexing underfoot and you knew they would last and look good for a long time.

Do you know if the one you saw was acrylic or cast iron? I read that the acrylic can stain easily …. I love the idea of a bench though!

Check the link I sent.

The ones in the hotel (same as one in photo) were cast iron for sure. It's going to be the most durable and stain resistant.

The one with the seat is acrylic. I like the idea of the seat also, but I'm not sure I'd give up the durability of the cast iron to get it. There are other options for seats including fold-down teak that don't look like a nursing home or free standing seats/benches that can be removed.

Oh yes great idea! Wonder if they can go in after tile is on the walls … thank you for your help!!

They will need blocking in the wall to support the weight. Get the install instructions before moving forward.

check out https://www.kaldewei.us/products/showers/ I've been happy with mine.

I’m trying to decide between penny tile and a basic plain floor in my shower to avoid grout. Is there a product out there that isn’t acrylic or white that stains easily?

Are you saying you're deciding between an all-tile shower with penny rounds on the floor vs. a shower pan?

If so, go with the shower pan. Yes, you can get good quality shower pans that aren't acrylic and won't stain. It will be easier to clean than tile. The shower pan will arrive perfectly leveled, and you won't be at the mercy of your tile installer's quality.