We visited the gardens on the first Sunday of October so didn't have to pay - free admission first Sunday of every month. You have to queue for a ticket and then queue again for admission which is rather tedious. Also be advised that there's a metal detector at the entrance : we'd brought a picnic and some cutlery from our accommodation which we had to leave and collect when we left!
Once in we thought the gardens were great: there's so much to see, from the amazing views over the city at the very top of the gardens ( a steep climb but worth it), the fountains and statues, tree lined walkways, two small botanical gardens with a variety of specimen shrubs and woodland areas.
There are lots of benches in every part of the garden - I don't understand where the reviewer was who said there's only six in the entire place!
If you're expecting to see a garden full of colour with herbaceous borders you'll be disappointed, it's completely different to an English garden, but that makes it an interesting experience. You also need to be prepared to walk a long way if you want to see it all; we spent over four hours and walked about five miles. A very enjoyable day.