It is widely accepted that at anything bigger than a walking speed drop, even R&G bungs can cause frame damage. Engine bars are even worse in a road-speed tarmac event.
Unfortunately I got hit sideways (left, on the coolant pump) yesterday evening. The bike went down on its right side. I have the sw-motech engine guards. They look impressive. But the right bar bent and is pressuring the engine cover. I see some engine oil drops, and I think the cover is cracked. And the clutch master cylinder cover is scratched. This was at slow speed, overtaking a stopped bus at a congestion in town. So I agree with Phmode: engine bars don't seem to be a good protection, they might even make it worse -- specially at the price they go for.
I won't even try to straighten them. I will remove them and get the R&G master cylinder cover.
I am not sure about "upgrading" the OEM bungs to R&G. If I had the R&G, I think it would have been worse for me. The car front bumper would have struck them and probably push me further to the right side. With the OEM one, it just grazed the left one lightly.