Yup they do seem to be good, but when you're battling away trying to figure out how to's (and failing) its hard to remember just what good value they are
Apart from the documentation there are also a few idiosyncratic uses of fairly well accepted properties eg AutoSize and the fact that they have duplicated identifiers so you have to use the unit to qualify them.
Finally being fair, whilst TMS don't respond on the ngs that well Bruno is good when you email support, and I'm busy converting my query generator and a major app to use them.