i've stayed in the owner's suite at la casa...it's amazing, to be sure. you've got a stellar private deck with a decent sized pool, all on top of the rest of the complex. the food at la casa was wonderful, we had delightful breakfasts and several wonderful dinners there, but we found the service great only as long as we didn't ask for anything special.

when we called to change our champagne delivery to a different--earlier--time, when we called about the sewage smell in our room (we were in another suite for several nights before being moved to the owner's suite,) when we called to inquire about the status of the upgrade/move to the owners suite...all those calls had to be repeated at least once, and in the case of the sewage smell, twice. they fell down on follow-through.

it's possible there's a bit of a language issue, as neither of us is fluent in spanish, but we were disappointed by the service. we were thrilled with the food, however.

one other thing about la casa, if internet is important to you (yes, i know it's a vacation ) the wifi doesn't work in the owner's suite, or at least it didn't as of a year ago, so you'll have to leave the suite to surf the net/check email. it works fine in the lobby, and it worked in the first suite we were in, but the owner's suite is too far away from the router, i guess.

what no-one has mentioned in this thread is the difference between zihuatanejo and cabo. i've stayed in both places (although in cabo i was at esperanza, not lv. esperanza still rates as our best vacation ever, but i digress) and they're quite different. cabo's more developed, there's more going on...zihua is a bit sleepier. we found the food off-site great in both places, but if you intend to do things outside of the hotel, you might want to keep that in mind. we preferred zihua as a town.

i did like the clientele at la casa, more well-heeled mexicans on holiday than a bunch of us americanos. not sure what you'd get at las ventanas, although as a post above points out, it's a beverly hills thing. la casa is NOT, which we did like. had we not asked them to go 'off book' a few times, it might have been a different experience.

let us know what you decide and how the trip goes!