Hi,
Better? Well, that depends on how you compare the plugins.
With Pixelyoursite, you can get your pixels running quickly. Less setup, less control, works out of the box.
With GTM4WP you will have more setup steps for sure since all your tracking is setup inside your GTM container on the GTM UI. It is handled by you, GTM4WP is “only” giving you the data to setup your measurement on the GTM UI more easily without the need to code by yourself.
But this setup with GTM will cost you more time.
There is a custom tag template for the Facebook pixel by Simo Ahava, that supports now getting ecommerce data from the data layer also provided by GTM4WP, it will shorten the time to setup a lot.
With GTM however you can have a more robust measurement setup with more flexibility and you will also need less plugins on your site.
If you would like to setup your pixels quickly and you do not mind having an additional plugin for that purpose, I would go with Pixelyoursite. If you would like to have more control, you have the knowledge about GTM itself then GTM4WP will be your friend ??