I currently have 17 (!) of these halogen spotlights (MR16/ gu5.3 I think they are, 12V) that are 50W each. I want to change these to LEDs. A couple of years ago I swapped one out with an LED (12 v also) to see what it was like. It flickered, burnt and then went off straight away so went back to the halogen lights and that was that. I would like to actually swap them out now as after having a smart meter installed, it has made me realise what they cost. I remembered the above situation where trying one died. After some reading around, it looks like for LEDs you need transformers as it is stepping down the voltage to 12v. The halogens currently there should have a transformer as they are also 12v. Do I need to replace the halogen transformers (not sure I even can, probably in the ceiling somewhere and I don't want to pull the ceiling apart) with LED specific ones or can they handle LEDs? I read LEDs are dc too whereas the halogens will be AC. I thought maybe the halogen transformer caused the LED issues. Maybe I just need reputable LEDs. These were some random brand off Amazon (Kakunuo).