Latisil Tile and Stone by Laticrete. It was what was recommended to me by the local tile shop, and is tons better than anything else I have ever found. It has been in my stick house for about 8 years. It is as perfect as the day I put it in, and does not mildew.
For installing, I recommend 2 things. Buy some blue masking tape, and mask off next to where your want to caulk. (or technically, where you don't want to caulk) Next get a glass of water and put a little dish soap in it. Do your caulk job and then dip your finger in the soapy water and smooth out the caulk. The caulk will not stick to your soapy finger, so you can smooth out the caulk perfectly and wipe away any extra. Once you get it looking pretty good, then lift the masking tape. That will give you a perfect straight line along each side of your caulking job. You need to lift the tape while it is still wet.
We have a local tile shop that has been in business since the beginning of time. This is what they taught me.
2004 AllegroBay 34XB Nov 2017 Banks, Front & Rear Trac bars, Konis
Sold:'83 Revcon Prince 31' FWD GM Performance 502 w/Edelbrock MPFI, Thorley Tri-Ys & Magnaflows, 4L85E 4 spd