Probably not - the difference between gold and higher are miniscule we are talking about 4-6% depending on voltage and usage.
The best is to get a power supply and only use at most 50% thats where all of them are most effective.
Obviously if you have 2K powersupply 5% matters, but in a 250W power supply 5% is well not as much - and price difference between gold and above are big, so you really need to be sure you have the correct size PSU first before you start thinking about Gold vs Plat vs Titanium.
So lets take an example - if you have a 250W power supply and only uses 50w you are at 20% usage. So if you save 5% on 50 wats, its not really a big deal (2.5 w)
But if the pico PSU is 100% effective (which its not, then you would save 10% compared to the Gold normal if we go by 90% efficiency @ 20%), which would be 5W saved - which again is not really a lot.
My point is - efficience matters most if you have either:
1. Many servers
2. BIG PSU's with high load