Best Practices - ReadMultipleItems vs SubscribeMultipleItems - by: davide

Dear OPC Labs team,
I'm a newbie and I want ask you the best practice to use a DA Client. I need to read tags (more or less 2k) and the ways to do it are:

• by polling using ReadMultipleItems
• by monitoring changes using SubscribeMultipleItems

At this moment I've implemented the "polling" way and it works great. If the tags changes frequently (more or less like to my polling interval) has sense to implement the other way (SubscribeMultipleItems)? Which are the main pros and cons?
Thanks in advance.