I have been testing those two extendo version for 2 months now, and posting results in my journal. So i think it is time to finalize a report here since less people read journals
I believe that mx288 works better than mx289. It last a little longer (perhaps up to 1 hour) and i can see more obvious “happy and carefree” hits. But by no means mx289 is bad, the difference is subtle enough.
The optimum dosage for both are 1.5 to 2 sprays.
I tried to blind test them, but taking off the label and put a sticker on bottom, so i only know which is which after coming home and verify (one bottle is randomly chosen and tested, and put in certain location so i can know which is which after).
I can tell which version i used about 70% of the time, not perfect but satisfactory since they are very similar.
Here are some older posts from my journal (long dont need to read )
I have MX289 and I am using it pretty much every day at 1-2 spray. Haven’t noticed a big difference to using regular Instant Shine except I have seen ‘Shine’ hits many, many hours after application. For example today I applied it at 12.15 pm and definitely received ‘Shine’ hits (usually people making a fun, silly comment/joke ) at 5 and 5.15 pm. This is pretty impressive work given that its primary active molecule, TAA, is so fast diffusing. The Extendo is working in that regard so far