I’ve been looking into upgrading uplink capacity on a Juniper EX4300 setup and came across the EX-UM-4X4SFP module. 

From what I understand, it adds 4x 10G SFP+ and 4x 1G SFP ports, which seems like a decent balance between flexibility and performance for aggregation or small data center environments. 

A couple of things I’m trying to figure out before moving forward:

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  How reliable is it in long-term production environments?
  
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  Any limitations or quirks when mixing 1G and 10G optics?
  
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  Does it actually make a noticeable difference in real-world throughput or is it more situational?
  
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  Worth considering given it’s already EOL (but still supported)? 

On paper, it looks solid, especially since it’s hot-swappable and designed specifically for EX4300 deployments, but I’d rather hear from people who’ve actually used it.

Would appreciate any real-world feedback, especially around performance and compatibility.