Biltmore, in my opinion is worth the price of admission. In addition to the house, which is magnificent in its grandeur, you can tour the grounds, the gardens, the farm and the new Antler Hill Village shopping/dining area nearby. In addition there is the Biltmore Winery which offers free wine tasting daily.
Biltmore is the largest privately owned home in the country. They take no federal money at all, hence the fairly high cost of admission. It is a spectacular place to visit any time of year, but particularly in the springtime. They have a flower and garden festival every year which runs through most of April and May with hundreds of thousands of tulips and other flowers planted around the estate.
If you are at all adventurous they offer Segway tours (one of the BEST I have taken as they let you go full speed...), Land Rover tours, horseback riding, and kayak excursions. There are beautiful walking trails throughout the property including a 1+ mile walk from the gardens down to the bass pond which takes you through the azalea garden.
Dining on property, while a bit expensive is wonderful with restaurants to appeal to many different price ranges.
The winery tour is very interesting and included in the price of your admission. The wine tasting is fun, and the adjacent gift shop makes it very easy to purchase a new found favorite.
If you do go, I recommend getting the audio tour in the house. It gives bits of information and wonderful stories of life for the Vanderbilt family when they lived in the house. I do recommend going early in the day, as it can get crowded especially during the spring and summer months.
If you need or want any additional information about Biltmore, Asheville or the surrounding area, PLEASE do not hesitate to ask. I love sharing all sorts of information about my town.
Linda