Apart from the casco viper & met parachute, are there any convertible helmets on the market?

how about the giro switchblade?

Do they still make it?

They've not made the switchblade for a while now,got mine about 2 years ago & they were discontinued even then. seems a very limited choice for that style.

I was going to go for the Casco then What MTB did a very bad review of it. Spoke to the owner of a shop and he says they are very "cheaply" made and don't look as though they would last.

Met parachute seems the only option but I just don't like the look of them!

Having had one for well over a year now, I just love my Met Parachute though some others have had issues with the fit. Try before you buy just in case. It's not too hot for the height of summer either, I use it all year round with the chin guard on. Looks a bit mushroom-like without it to be honest.