I had Midas put synth in my 2006 RAV4 on a whim a couple of times around 2010 or so, I think they used Valvoline but I'm not sure. They told me that I could never go back to conventional after that, but even then I smelled a strong whiff of BeeEss on that one. I know that a statement like this opens me up to ridicule, but the RAV4 felt "slippery" to me after the first synth change...it's hard to explain exactly what I mean, but I have seen other people online use the same term for the sensation and it was the term that came to mind when I first started driving the car. It sounds insane and I can't explain it, but I went into it thinking that the oil might just last longer and was shocked to find myself thinking the car had a different feel...I almost wanted to have the stuff drained out at first.
My first DIY change, which was also my first with synth, was in 2014 with M1 5W30 in my '14 FXT.