I agree -- I have a friend who tiled her vacation house shower floor with them, and while they look great, they're really not nice to stand on.

Mesh-mounted rock or pebbles are very popular for shower pans, but if you are unsure if you will like the irregularity, you can also look at smaller mosaics. Natural stone (tumbled marble, travertine, etc.) has a good texture to them for a pan. Grout is a helpful element in the shower pan, and if you do sanded grout it adds even more texture. You obviously want a non-skid texture in your pan. I personally like the look of these when they are all grouted in, but it also depends on your other elements/surfaces.

Here are a couple tips.
http://www.diynetwork.com/how-to/how-to-lay-a-pebble-tile-floor/index.html

Almost did it....love!! The look...but I closed my eyes and thought of standing on them as I enjoyed my shower....and chose not to....and am super glad I didn't....but I do love them!! Try on the wall...as an accent trim

Cheryl, if you're unsure if you will like the uneven texture, why not buy a couple of sheets, put them in your shower and try standing on them while you shower?

That makes so much sense what Bobbi said. I totally think that you would love it. I got pebble tile on my bathroom floor and absolutely love it. It is not hard or bumpy. I do not regret buying them. I think that I am getting a massage on my feet daily. http://www.modwalls.com/modrocksrecycledglasspebbles.aspx

I think I would love it too! I wonder.....if you could put a bunch of the 12 X 12 sheets together, could you put it in the bathtub? My shower has a bathtub but I'd like to try it!

Bobbi-the money was well spent. It is the best part of the bathroom along with the bench of course. I have not tried to sit on them so I cannot answer that.

Angela, yours look like much smaller stones, they wouldn't be so hard to stand on.

https://www.houzz.com/photos/pebble-floor-phbr0lbl-bl~l_71852
https://www.houzz.com/photos/pebble-floor-phbr0lbl-bl~l_71852
https://www.houzz.com/photos/pebble-floor-phbr0lbl-bl~l_71852
https://www.houzz.com/photos/pebble-floor-phbr0lbl-bl~l_71852
https://www.houzz.com/photos/pebble-floor-phbr0lbl-bl~l_71852

Kimdee, yes they are smaller and actually recycle glass. I fell in love with them when I saw them. Pretty pricey too but so worth it.

Bobbi-I actually sat on the floor this morning and surprisingly it was not uncomfortable. The hardest part was getting up of the floor and frankly not fun on the knee.

A little texture is great, but too much is not ideal. See our video for what we do to insure you get an optimal pebble surface. Thank you
http://www.islandstone.com/videos.php?id=4&keywords=Pebble_Tile_Quality

Thank you for all your answers/ideas; this will be in the main guest shower which hubby will also be using; I may use it once in awhile-more a bath person ... I will be putting a free standing tub only in the master bath area, the bathrooms are right across from each other so we will have a "barn door" on our side for his use and just close that off when we have guests.. lots to think about when planning a new house; the last one we buildt was 23 years ago.....