Honestly, the above "Manual Trim" sounds like marketing tripe.
From the manufacturers of Sandforce controllers (and interestingly, quoted on the Disk Sensei website!), "Garbage collection without TRIM will always be moving all invalid data during the GC process acting like the SSD is operating at full capacity. Only the TRIM command can identify the invalid data and improve performance"
Trim is a specific instruction that is sent to the SSD and the Apple driver doesn't send it, period. A modified driver (kernel extension) can do, but to load that you need to disable kext signing.
All modern SSD's do garbage collection. Without being sent the Trim command (which the Apple driver will never do), they don't know what is real data and what is not. "Manual Trim" writing zeros into available blocks will not help, since the drive has *no way* of knowing whether this is real data or not. It will run garbage collection on all the data, including the pages of zeros; not helpful at all in reducing write amplification, which is one of the prime benefits of Trim. In fact it's downright detrimental since (a) you are needless writing garbage to the SSD in the first place and (b) the SSD then has to do lots of reading and writing to tidy it all up. I would suggest this "Manual Trim" option - which is not Trim at all - should be avoided.
You basically have 2 simple choices; either disable kext signing, which the inherent (but not enormous) risks that involves (previous OS X versions didn't have kext signing anyway); or let the drive manage itself and accept that it will wear out somewhat faster and may not perform at its absolute best.
Whether these last two drawbacks matter in the real world will depend on what you use the drive for. If it's for mainly read-access with little writing going on, it probably doesn't matter at all. For a boot drive, I think it does matter.
There is a 3rd, more invasion option however, which is to periodically wipe the drive with a ATA Secure-Erase command, destroying all data and returning the drive to factory performance levels. And then restoring from a back up. You could do this every few months if you wanted to.