I love wax melts as I think they give a stronger throw than a lot of candles. I love Yankee Candle wax melts, both the single ones and the bigger packs sold in Tesco, Sainsburys etc. I've also seen some Yankee Candle wax melts in Home Bargains.
I also like the Aldi wax melts which are a dupe of the Jo Malone scents especially the Lime, Basil and Mandarin.
Home Bargains sell Wickford and Co wax melts which I think are a dupe of Yankee Candle and I always find these fill the room with scent really well.
I saw some wax melts in Primark after lockdown but they don't seem to stock these anymore. I don't rate Primark candles but the wax melts I tried were good.