I did the DIY self service. Not too difficult if one is somewhat mechanically inclined. They have a really good video (Paul did it I think) and I suggest you watch it before starting or even ordering. This will give you an idea of your comfort level. It really isn't hard nor time consuming.
I watched the video, was ok with it, placed the order for the self service kit. It arrived within 2 days. I watched the video again before starting then had it running while I followed along. I would watch for a few, pause, then do the work, then start, etc. Maybe took me 45 minutes if that.
Nothing stands out to me as being difficult in the overall process. It comes apart pretty well. Goes back together just as easy. Honestly no stress at all. Also note please do this just before all of your reagents are out what is in the tray. It will be best if you have a 2 month kit ready to go and a calibration reference. After it is done and running I calibrated about 48 hours after it was running.
Edit: apologies, I left off time of ownership / running of trident. I purchased it around February or March of 2020 which puts me at 2 years if not a few months over. I may have bought it in January but I can't find my exact notes. I'm sorry. Also not sure if it really needed it but wanted to do it at least once as my ALK started to trend down even after calibration. Turns out my dosing lines where the problem

Anyway hope this helps. Sorry again for leaving out this detail.