We should get some guys from Ben-Air and Kato-Air in here to talk about ice and single engine aircraft.
Even in a de-iced turbine a/c it can go really bad, really quickly.
(I think we both know a least one Caravan incident deice!)
I really like to know what knowledge you can have 540, that makes it possible to determine that the 2000ft cloud layer you want to climb trough won't bring down your aircraft.
I've seen a jet trainer collect enough ice trough 3500ft of cloud to make it almost uncontrollable, in clouds that where supposed to be without icing.
Same clouds in even a high performance piston? Breeze block?