I've done loads of beer kits. I don't drink lager, so I can't recommend one, but my favourite bitter kit is (currently) Festival Golden Stag Summer Ale, and I'm currently drinking a very good (and strong) St Peter's IPA. The Woodforde's range cover bitters from light session ales (Wherry) to heavy porter-style (Nog or Nelson's Revenge) and are easy to brew if you have the right equipment. Patience is a must, though, and although you can brew a drinkable ale in a fortnight, I generally allow two weeks for fermentation and four weeks for conditioning, making six weeks in all.