[k0n2ad]

There are too many points on the path where something could go wrong. Given that this is the first time that I am hearing about Google Calendar being a problem, I doubt it's the actual problem. What email service are you using?

[cool-RR]

It doesn't even let you specify an email address -- It just sends to your associated Gmail account.

[newsio]

I use Google Calendar alerts and have regularly noticed late email notifications (up to an hour or two), but never failed deliveries. I use Yahoo mail.

[cool-RR]

Possibly you don't use it as heavily as me, I have maybe ~5 reminders a day.