I tried out Gold for the first time this past season b/c I wanted a table seat at Cabaret, and the seats have been great. Standard HipTix usually gets you the last row of the Mezz (and in some cases I think last row of the orchestra, which in Studio 54 is almost always partial view). With Gold the entire Mezz opens up for you and the side sections of the orchestra.
I had great table seating for Cabaret, with the table on the aisle, first one in the elevated orchestra section. Front row orchestra seats for Indian Ink. Front row Mezz for On the 20th Century.
Its obviously better to buy in advance to secure your ticket. However, sometimes the day before or day of a performance some unused subscriber seats are released and can be purchased with hiptix gold. So it is possible to score last minute tickets if you are actively checking the website. (Unfortunately, they dont let you move seat locations. After buying ok mezz seats to the Real Thing, some great orchestra aisle ones opened up the day of and the box office refused to move them. Not the best policy for paying subscribers but whatever).
I was still waffling on signing up and paying the extra money for gold this season, but with the cast of She Loves Me...I just need great seats for that haha. I would go for it if you are interested in the season.