I've recently installed an em-trak on another boat and it was fine. They got it sponsored on account of being Youtubers with a bunch of followers.
Our Matsutec is also still fine after several years of cruising and cost a lot less for people who aren't being sponored
Simrad/Garmin/Raymarine ones are generic circuit board designs with a branded plastic case and best avoided (in case you ever wondered why they all use the exact same ProAIS software, that's why). They work but you pointlessly pay for the brand without getting any benefits out of that. Em-trak uses the same board, but had competetive pricing last I checked.
You'll want it to have the right outputs for the rest of your system, which means choosing between NMEA0183 and N2k (some have both). Then you can pick if you want a USB output, Wifi output or even Ethernet (or combinations thereof). If you choose Wifi, make sure it can either act as AP or join an existing network, else if you expand later you'll be stuck. Some have SD card slots for recording your tracks but I don't really see the point of that.
Ignore any marketing waffle about Class B, B+ or A, it makes no practical difference. A good, well matched antenna makes a big difference though. You can buy a AIS specific antenna, or you can take VHF antenna and clip a (carefully calculated) bit off the top to match it to the AIS frequency, which helped a surprising amount. Also the antenna should be installed as high as possible and clear of obstructions, yet well away from the marine VHF antenna. Ours lives on the stern arch, which seems to do well.
Active antenna splitters for running VHF and AIS off one antenna are absolute garbage and must be avoided. They
break all of the time. I've seen so many dead ones and the Simrad ones failed in a silly way where the AIS path got locked in and therefore the marine VHF stopped working completely. Just don't even think about a splitter. Simrad boat gave up and fitted another antenna after the third warranty replacement.