If all you are doing is watching region A BDs on your player, I doubt it would be worthwhile buying an Oppo. If you are watching DVDs, the Oppo might upconvert them better, but upconversion seems to have gotten much better in recent years, so I would not be surprised if that was not dramatically different either.
Now, the Oppo will play things like SACDs and DVD-Audio discs, so if you want to play such things, then it would make sense to get an Oppo. Also, on eBay, people sell kits to allow you to change the region of the player for many (or all?) Oppo BD players, so if that were of interest to you, then it may be worthwhile to get an Oppo.
In my case, I have an old Panasonic BD player, and will probably buy an Oppo after it dies, because I do care about other regions and about those other discs. But right now, I don't need it (I have an old Oppo DVD player to take care of everything except non-region A BDs, of which I presently have none).
Another thing that is good about Oppo is that they are good about updating firmware as needed, so it can be a good long-term choice. But in your case, I would not bother unless you want to play something your current player cannot play.