It really is quite similar to what Ph.D.'s look for, with a bit more leeway with the amount of research you've done. As for what is more attractive to a Psy.D....a masters thesis or placement, I'd say thesis, as research is still an important part of the training. I'm not discounting clinical experiences, it is just hard to get experience in an area that will give you as big of a leg up. I know someone who gained experience using some simple assessments (BDI's, BAI's, etc) under the supervision of a clinician, and someone else who did work with drug rehab....and both experiences enhanced their application as they could show a direct relationship to their previous and what they wanted to do at the doctoral level (assessment and substance abuse work, respectively). In those cases, it made sense to have the practical experience instead of a more research focused approach. I like the thesis idea because it will get you use to the kind of work you are expected to produce at the doctoral level.