if you buy one, youll buy a second one. to be honest, youll get addicted, youll want 2 whole sets and then an additional keg (so 2 fermentation buckets and 3 or 4 kegs) and then youre away. you can then make 40 pints for under £20. this means if you have a load of kegs you can get your mates round in the summer and host your own beer festival