we're spraying marmorit presto at the moment and thats lovely gear to spray , you can spend some time ruling it and getting it nice , it stiffens on the wall after its been sprayed fairley quick but a quick flatten in with the trowel brings it back , and it hold up well over night , we find it better to use 10mm beads rather then 15mm with it though (but you need to dab the beads up rather then dryfix them)
havent used parex for a couple of year but only used their GF which is really fine but i thought it was great gear to use and cos its so fine you can get it really flat with I section