I grow most of my cacti and agave in containers that hold more than five gallons in a mix Tapla would consider pudding. I use one part native soil, one sand, one pumice, and one compost.
When it's over 100 degrees every day, mid May thru mid Sept I only water every two weeks and no water at all mid Nov thru Feb. None of my pots are in full sun all day.
Are my plants reaching their full potential? Probably not, but I already spend enough time watering plants.
Euphorbias do not like this mix.
Here's a few examples:{{gwi:414271}}
{{gwi:414273}}
{{gwi:414276}}

{{gwi:414279}}

I do a modified version of the gritty mix for most of my plants, they just seem to do better. The mix includes a quality cactus or potting mix, coconut bark or coir, pumice or turface and perlite. You can experiment a little to see what works best for your plants. Phoenix is way too hot and dry to use the full mix, although I'm sure some would disagree.

Very nice collection, Jon!

Fun question! Great plants, Jon, I love them. I use a quality potting mix mixed about 1:1 with pumice for most of my potted succulents. I water them fairly often, in my opinion, lol, so the extra pumice helps prevent rot. If you water less, then you could get away with more organic material and less pumice. It all depends on the light, the plants, and our watering habits. Fun to hear who does what, though.

Let us know what you decide to do and how it works out. Happy gardening!
Grant

Here is a link that might be useful: Pics from my garden, August 2014

I'm in Vegas, which is a little drier, but I can't do vanilla Gritty outside for anything -- even cacti and sux. I can do Gritty inside.