Can't comment on Luton as I've never flown to murcia from there.
I live near East Midlands airport so use that pretty much all the time, usually the 5th of November has been Ryanair/EMA's cut off to murcia and beginning of winter service it resumes again around easter, it looks like the date has been moved forward to the 25th of October, I've use Alicante during the winter as a result, it's only an hour away and there are some good deals into there.
This message was last edited by RichA4 on 19/05/2014.