hey, i'm also thinking about using my suite upgrade cert at the grand hyatt taipei. i called the hotel on monday and asked them to clarify a few things -

1) you'll be upgraded to a "grand" suite. i think they have about 35 of those rooms and was told that there's plenty of availability on the day of my reservation (may 5). the "grand" suite used to be called a "junior" suite. you can see a picture of it on the website.

2) they would not confirm it over the phone and told me that the upgrade is based on availability upon check-in.

3) eligible rate must be paid, as stated on the back of the cert