Yup. I've used both a CCW (LDA, single stack, commander slide on officer frame) and an SSP (SA, single stack, full size). The former is my daily CCW piece, which is why I often use it in IDPA -- for really "practical" practice. Neither is really set up as a competition gun, but both work great. They're plenty accurate and 100% reliable.
Note that the LDA system is not the quickest. It is indeed very light, but it has quite a long trigger reset. Any of the SA or DA/SA pistols can be made to run faster, except in the most highly practiced hands. Also, you lack the second strike capability of a true DAO design. If you're familiar with Glocks, however, you'll know how to use the LDA, as they are quite similar.