I know a few people who have taken it and all seemed happier than with spiro, but the thing is, most people don't really like spiro's ancillary effects. I know lots more people who take flutamide, androcur or bicalutamide when looking for an alternative to spiro. Now, I don't really know all that much about the specifics of zoladex (goserelin acetate) but, it would worry me a bit, that these other alternatives seem more popular than it. That isn't saying that it is good or bad, but I would want to try and figure out why it isn't a more common choice.
To be totally fair though, I don't understand why spiro is the most common choice since for me at least, it started to give really annoying side effects with it's diuretic effect and outright dangerous effects from the lower blood pressure. Lots of people could get really hurt if I were to faint at my job.