FWIW, this is an XP system which does some heavy video editing. Samsung utility provides software "TRIM" and strangely schedules it (I don't know how or when, but it does seem to run on occasion. No way to schedule it as in older versions).
Installed: late 2013
Written: 21.58TB
I also put a mSATA into my old laptop via a mSATA-ATA adapter, this one is basically TRIMless and there is no dispute that it's slow - but only relatively so; it beats the pants off the 2.5" drive it replaced.
For old computers, I don't think the choice is always straightforward. SSDs (the ones I've used) have weird latency issues. As in, access time is great but every so often the things will go to lunch for a couple of seconds, causing odd lag in some lag sensitive situations. I've never seen that with an electromechanical disk, which are slow but consistent. They just work. It even happens on this system, which wasn't built as some hobbyist souvenir, but for use. Once in a while, between tasks, the system just takes a coffee break for a few seconds like it's writing a cache or something.
My vote is it's certainly worth it for performance. But you don't always do everything for performance. I picked up a P100 last year. I could easily put one of my P233s in it, which greatly improves its responsiveness. Yet, I don't. That also speeds through a lot of stuff you used to sit through. Or going on-line. I used to do that in Windows 98. I'm not going to lie, there's a part of me that wants to relive the waiting at the analog modem connection dialog for a minute. It was annoying as hell, but it built the suspense and gave you this weird feeling of being in a special place, arriving on the internet, where the possibilities were endless. Maybe you want to see the loading screens, if your goal is to have a "period system." If you just want Windows 98 software to run ultra fast, of course, the SSD is a prime choice.