Andrew C said:
Do a search on the problems of an S1 visor. It is simply dangerous in rain, particularly if you wear glasses. Don't believe all the rubbish that 'it was just a bad batch'. I've had replacements and they were all shyte in the rain. The only reliable cure that I've heard of is a pinlock visor. They are not cheap which for an already expensive helmet is bollox service.
Unfortunately I have to concur with Andrew. I'm one of these crazy people who commute on a bike in nearly all weathers

and my Schuberth S1 is pretty much unusable in the rain below 60mph. Above 55-60, the airflow through the helmet clears the visor OKish (it doesn't manage if the weather is cold) but as soon as I get into London 60mph are only a distant dream so the visor starts fogging up.
Then you've got to open it, water starts running down the inside of the visor. You close the visor again and it mists up even worse where the water has run down the inside. Only cure again is to go over 60mph and fly blind for a few minutes until the visor is clear.
I fondly remember a ride home in where I turned off the motorway near Leeds castle to enjoy the backroads even though it was p*ssing down. I was also rather cold. The rain got worse and five minutes later I couldn't see anything - had to ride home at 40 mph with the visor open. Now I'm four-eyed so the ride home looked something like this:
- Ride a bit
- Stop to clean glasses
- Ride a bit
- Stop to clean glasses
- Repeat ad nauseam
So muggins here fires off an slightly annoyed email to Schuberth, gets an email back saying "Please send in helmet, well check it over for you".
Jolly good, thinks I, all I need is a helmet to tide me over while the Schuberth's away. As I was buying an 1150GSA at the time, the BMW dealer did do me a good deal on a BMW Sportintegral, one of the very few helmets that fit me properly.
I think you can guess what's coming - the SportIntegral is made by Schuberth and suffers from similar problems
The Schuberth is already on the third visor and now (after about 18 months) the sideplate is worn to the extent that the visor snaps out of it if you open it fully. It only took my local dealer about 3 months to get new side plates...
TBH I'll keep the Schuberth for summer as that's what it's good at but I'm now looking at a Shoei XR1000 for rear-round use.
If you don't ride in British rain and not below 10C, it's a good helmet. Unfortunately I do both, sometimes even at the same time...