Art,
The FX-23 is a well battle-tested anchor model that will perform extraordinarily well for you in common sand, mud, and clay bottom conditions.
This model was called "the Champion of All Categories" after a test conducted by Voile, a French sailing magazine, when it held to over 350x its weight which was far superior to the other aluminum and steel anchors in this test.
Here's a short video from this test when this 7 kg (15 lbs) anchor held to 2510 kgs (5,500 lbs). If you happen to know French, please pardon the language:
Safe anchoring,
Brian