Re: LED Bulb price
LED bulbs seem most immediately useful as a replacement for halogen spots. Although not a like-for-like comparison, I don't think I ever got all three GU10s lit in my old kitchen for more than a day or two (even after changing the light fitting), when we installed kitchen lighting in the new house we went for 6x LED AR111s and they've been happy for over two years. Relative cost of an individual bulb is incomparable of course, but when factoring in the hassle of regular bulb replacement it's far more attractive.