The biggest thing trim does really is pre-erase blocks so those drives capable of fast writes can do so without being interupted by slow erase cycles. Older ssd's aren't actually capable of fast writes to start with, especially when the problem is smaller writes, that its not actually being hampered that much.
Either way, trim, outside a few benchmarks, makes very little difference anyway. Before I had trim I noticed no detectable performance loss outside of benchmarks, the solution, don't benchmark it. Since adding trim(and since removing it so I can raid again) I saw no appreciable difference in general use or installing games or anything pre/post trim, again except in benchmarks I couldn't notice the blind bit of difference.
Saying that I'll still eventually stick garbage collection enabled firmware on my crucial drives in raid 0, it essentially runs the trim function from the firmware itself when idle, because why not, I'm certainly not desparate for it nor care if they never added it.