I see from your "current tanks" list you have a 40g salt tank. Is this a 40 breeder?? If it is, that's one of my favorite tank sizes, large or small. Right now, most of my free time is dedicated to upgrading or something with my own 40 br, which is a little cramped. Point being, what kind of lighting do you have? IMHO, even with vho or compacts, a squamosa will probably do fine on the sand--a 40br is only 16" deep.
Also, I've personally tried to get my squamosa to attatch to rock with no success. The croceas and maximas have no problem; it seems that the (very) small, almost nonexistent byssal openings of squamosas keep them from attatching quickly. At least, in my limited experience. Within a couple weeks on a rock, all my maximas attatch themselves quite firmly, as with the croceas.