I would like to endorse Cyclic Hotlines remarks about the caravan without reservation.
I have a litte less time on type than he does, and never felt the slightest qualm about operatng SE IFR on sectors up to 550 miles over some of the most inhospitable (and unpopulated) terrain in Africa where SAR are only letters in the alphabet and we carried goolie-chits as insurance.
SE IFR would open the UK and European commercial aviation wide at a level it has never seen before, huge, huge opportunities are available for market expansion if this is allowed and as others have said itseems there is little if any evidence to suggest this would be more hazardous than any other form of aerial operations.
My one caveat would be this; SE IFR is no place for brand new inexperienced pilots. I would hate to see this innovative way of bumpstarting entry-level commercial aviation (from a commercial aspect) hamstrung by a requirement for an utterly unnecessary second pilot - SP is as critical to this as is SE, but this will never be a job for new CPLs. This, I guess, will be the challenge to the new SE operators - finding pilots with sufficient experience to do the job on the low rates of pay likely at this level of the business.
I sure hope they get this right. The Caravan was the best start to a siezed wing career that I could have wished for! I'd wish that luck on scores of others too.