I like simple things that are built to last.
The beauty of the SS reels, if you buy a decent set and don't make a habit of dropping them, is that they will last you a lifetime. So one day, when nobody is making decent film processing equipment anymore, you won't be caught looking around for a new set of reels.
SS reels/tanks also don't absorb any chemistry and are simple to clean and dry, so carry no real risk over time of chemical cross-contamination. Not sure if plastic gear does, but SS certainly doesn't.
You will never break or crack a steel tank.
If you spend a bit of time practising with SS reels in the daylight, and then in the dark, you will soon get the hang of loading them in a way that works for you and will never have any trouble doing it in the darkroom.
If you decide to buy more reels, I think second hand ones are a gamble. I would forego a couple of beers or coffees and use the few bucks saved to get new reels.
Having just posted this, I see that Thomas has just made some of the same points... great minds think alike!