The problem is not many NiMH cell manufacturers provide the cell information on the casing or in a brochure. There are plenty of NiMH packs out there, being sold to unsuspecting retailers and pilots, that are not really up to the job reliably. We only find out when something goes wrong.

Any system is only aws strong as its weakest link and as you say, why risk an investment in RC with substandard battery packs? I agree, hence I prefer to fly with LiFePO4 (Hyperion or A123) because I trust those as I have not had a single issue with any of the two cell packs.
They're safe for Ignitions and Rx but adding a diode just keeps things nicely under control.

I'd rather that than trust a 4cell NiMH pack that decides to drop a cell on you midflight...