RJ10

If you have a ubiqiuty UGX or dream machine (or switch) this is the SFP to buy - This is plug and play and will work on 2.5, 5, 10Gbps.

These are actual decent and stable transceivers, no connection issues, they don't lie about what they are in the firmware and properly report temperatures, speed, etc. Expensive, but I haven't found others that work as good as these...

I use this SFP+ module on my Ubiquiti UDM Pro WAN port. This module, as opposed to others, can negotiate different speeds on the SFP+ and ethernet sides. This lets you take a 10G only SFP+ port (like on the UDM Pro) and hook it up to a 2.5G Ethernet device, like my Comcast modem. This allows me to take advantage of the overprovisioning (1400 Mbps) on my xfinity service. Note that this works on other devices, too. I have also used it on a Brocade 10G-only SFP+ port with another 2.5G ethernet device. No issues with either application. There might be cheaper alternatives, but Microtik is a well-known name and the module worked well enough for me that I bought a second.

On the pricey side, and they run ridiculously, hilariously hot (95-105C), but they can reliably push 10GaseT though the existing Cat5e runs in the walls of my multi-story house, where no other SFPs I've tried have been successful. I only bother with these for long in-wall runs - cheaper knock-offs (e.g. Ipolex and 10GTek) work fine for short 3-6 foot patches, e.g. between a switch and a PC, and run much cooler. If you've dismissed 10G as not being possible in your setup due to old wiring, it's worth giving a pair of these a try. Note that if you're not constrained by existing wiring, though, you're almost certainly better off using fiber instead of twisted pair copper - it's generally much cheaper and easier all around when dealing with 5-10 gig networking.

I purchased this transceiver due to the fact that it provides the best throughput and stability compared to other transceivers on the market. Other adapters seemed to either have issues with upstream speeds, or with flow control issues at speeds between 1Gbps and 10Gbps (2.5Gbps being the most common). I use these with Ubiquiti Dream Machines and Gateways, as well as with Mikrotik CHR on an x86 hypervisor. Now, there are newer transceivers out there which can handle longer cables, and which run cooler. This is still my tried and true transceiver until I find a better one. This Mikrotik transceiver can get hot, so ensure it is given adequite cooling, and avoid placing these next to each other in adjacent slots unless there is space in between to allow for cooling.

This MikroTik S+RJ10 was the only SFP+ RJ45 module I was able to get to work with AT&T 5 gig fiber internet. My setup is AT&T BGW-320 gateway -> Ubiquiti UXG-Pro. Originally I purchased the following SFP+ modules from reviews on Amazon, Reddit and Ubiquiti forms: B07P39G4XJ Wiitek SFP-10G-T B01MS8OXJ8 10Gtek 10G-SFP-T(Ubiquiti-1pc) B089D1ZYCJ fiber mall UF-RJ45-10G These 3 SFP+ all connected and had good download speeds of around 3.7-4.7Gbit, but the uploads speeds were around 300Mbits and sometimes reach 500-700Mbits. There are others having similar issues with the UDM Pro and someone on Reddit was able to find this MikroTik SFP+ to work. I got delivery of this product today and was able to plug it into the UXG-Pro and get my uploads speeds greater than 1Gbit. My setup is MacBook Pro M1 Max & HP Book Firefly 15 G7 (WIN10) -> B07KTLP44W QNAP QNA-T310G1S -> Ubiquiti DAC Cable (included with UXG-Pro) -> AT&T BGW-320 Wiitek support was very responsive, but the UXG-Pro was a newer product they haven’t tested so they suggested I contact Ubiquiti. I’ve tested the SFP+ Module from the QNAP to the AT&T gateway and the MikroTik was able to support the fast download and upload speeds, the other 3 only supported the fast download speeds and had similar issues with the uploads speeds averaging around 300Mbits

The transceiver works as expected, but! it gets really hot. I noted in the router; warnings every 5 min about the temperature of the transceiver. > sfp-sfpplus1 high temperature warning! Please, improve module cooling/placement I had to get a fan system to sit my router on to cool it down. This is apparently a known issue though. So if you are getting this for a passively cooled router, add a fan!

Excellent product that provides just what I was looking for. I have a Unifi switch with a 1G/10G-only SFP+ port (that is, the switch's SFP+ port does not support 2.5G or 5G natively) but a Unifi router that has a 1G/2.5G RJ45 port. I wanted to be able to connect the switch and router at 2.5G. Most 10G SFP modules will only support 2.5G if the SFP+ port itself supports 2.5G; I tried others in this configuration and they didn't work at all. However, this one works great for my purpose. (Presumably it also supports 5G, but I don't have equipment to test that on.)