terriks is right--a properly built & waterproofed shower won't leak. Our shower/tile guy was meticulous on this point. Acrylic is more difficult to clean IMO--especially those textured bottoms. So my vote is for tile hands down.
As far as keeping it clean...there are several things you can do now in the planning & building stage to help with this:
1) Use larger tiles (12x12, 10x13, 9x18, etc). Larger tiles mean less grout.
2) Use a smaller grout line--1/16" or narrower. Not all tile can do this. Stone tile typically can and certain porcelain/ceramic tiles--it has to do with the type of edge the tile have. Your tile guy can help you with this. I can tell you from personal experience that Florida Tile's Pristine & Renaissance styles will work for this.
3) Use unsanded grout--sand in the grout gives anything that wants to grow a place to hold on and grow. Unsanded helps eliminate this and also has a smoother look.
4) Put a squeegee in the shower and use it after each one--helps eliminate things growing as well as water spots.
Hope this helps!
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Shelf in 2nd floor bathroom
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