We changed to LED light bulbs last year when we moved into our new house. We bought them at the local DIY store and yes, they were expensive, but as they are supposed to last for thirty years and we are both over 60, we assume we won't be buying all that many light bulbs!
I discovered this winter that you have to be careful when screwing them into a light fitting that it does not unscrew itself while you are putting in the new bulb. If it does the new bulb certainly does not last 30 years - 30 hours is more like it.
Apart from that we are satisfied with them, and we have saved quite a bit on our electricity bill, but as the company that supplied our electricity has been amalgamated twice with others in the year and a half we have been living here, and as all our new electric equipment, washing machine, dryer, vacuum, freezer and fridge are ones that use the least possible electricity, I can't really work out how much of our saving is due to the light bulbs.