Hi, i am in the process of building a custom site in php. I am designing the user's notification settings and i am trying to decide on what options the user can check and uncheck in their settings. (please do not suggest open source software as this site needs to be custom for many reasons

i have added the following setting, and i am trying to decide whether to leave it their or not:

[] email me when another member comments on the same post

I am aware that some posts will have 500+ individual comments so that means that if all of the users have the above option selected, the system will need to send out 500+ emails to all of the users, everytime someone adds a new comment.

Would this slow down my system or is PHP well able to cope with these type of functions these days... thanks in advance for your help...