Hi, I was on the Screwfix website today and noticed they sell a 250w metal halide bulb with an RX7 fitting. These bulbs surely will fit into any halogen lamp with an RX7 fitting. Has anybody tried them? Or am I barking up the wrong tree and they are no good for exposing screens? It would be nice to know as Im using halogen and wonder if its a cheaper alternative to going for a full halide upgrade.