Share 'Halogen incandescent V Traditional incandescent'

Hi all, this is not a question fot the pureists amongst you, but has anyone tried using Halogen incandescent instead of Traditional incandescent. I understand that Halogen incandescent give out more heat than traditional which are being phased out (I know available still) so assuming a slightly lower wattage would be OK. Has anyone worked this out for 40w replacement