Just a few comments.
What the above posters are trying to say is that expectation bias isn't always logical, and is sometimes counter intuitive. Saying you weren't biased may be a subconscious clue that bias actually exists. Whether you think you are biased or not is really of no consequence. When you spend money on audio gear, regardless of what you think you feel, subconsciously you are expecting some improvement for the outlay. And your mind will surely work to justify the outlay.
Sometimes when I listen to something new I am also initially "blown away". It wears off and reality sets in, sooner rather than later, especially when you try to match levels and listen critically. One trick I try to use is to deliberately set what is thought to be the more inferior component to a slightly louder volume setting. Then if I compare the two components and the inferior unit still sounds worse, there is a good chance the difference may be real and its time time to investigate further.
Blown away is such a badly overused term, and it really means nothing. Is my "blown away" the same as yours? Or is mine a bigger bang? Too often for me, being blown away is due to my mood on that day.
If you hear a difference try to get specific about what it is you are hearing... very specific. That process in itself often reveals the truth. I've used this tactic with several friends who were convinced that vinyl was completely superior to digital, hands down. When pushed to describe the biggest difference and then point it out by switching sources in real time, they cant. All of a sudden they cant hear the difference anymore. But in spite of this, they still leave convinced that vinyl is all that and a bag of chips. Such is the power of the human mind. After all, you do get snap-crackle-pop and a large version of the album art. But if they are happy, why rock their boat?
There is nothing magical about the machine. Now, those wooden disks and high end power cords... those are magical.
Oppo always recommended a 103 for use in systems where the HDMI output is used, allowing the DA conversion to be done outside of the player. For instances where the player was used to decode, the 105/205 was the recommendation due to the additional focus on the DAC performance. So, if you think the 103 is the cats meow, a 105 or a 205 should surely send you off into Nirvana.
For my part, my days of playing physical disks are long gone. No more investment in physical disk players for me. I buy the disks, rip them immediately, store them, and never play them again. If i could get MC downloads, I would go that route in a second. The only exception is a the rare playing of a video disk to watch, and with the emergence of all the on line streaming services, I don't think I've done that in several years either.
But for the record, your Oppo seems like a great machine, especially for the price you paid. And the icing on the cake is, it can rip SACDs. Enjoy. And if you feel it sounds better than the rest, that's your business.