I've also stayed at all three Marriotts and the Renaissance.

I was less than impressed at the north and DT properties. Clueless staff with the personality of a brick. Room was is poor condition downtown and the north property had the most terrible restaurant service I have ever had.

The "airport" south Marriott (not really at the airport) was nice and I found everyone to be friendly. Nice room, amenities, and services. Looked new/renovated about two years ago. Really enjoyed it.

The Renaissance was truly a cut above though. Very classy and wonderful service. Room was decorated nicely and its in a good area to do some walking and shopping.

You should not be dissapointed with the hotel itself in Round Rock (Austin-North). Everything is in good condition and is clean. Just the staff and extra stuff could use some fine tuning.

Enjoy!