You'll get good to excellent wines at decent prices. Many of these wine clubs are (or were) outlets of the same company, Tony Laithwaite's at Theale.
The problem I had was delivery. With another merchant the problem became so bad - e.g. wine not arriving when you've taken the day off work, wine arriving unannounced and left poorly concealed in the front porch - that I completely abandoned the method.
There is a good chance you'll get something outstanding in a starter pack. The first time I went with Bordeaux Direct I received 2 bottles with such pretty labels (!) that I kept them for a few years, ultimately giving them away as presents when the wine was valued online at �60 per bottle.
Have fun.