I was - and am - in a similar situation: Some 2 months ago I purchased some used IE800 for $200, only to realize with the help of the fake IE800 thread, that mine were fakes. After first having been extremely pissed off, I noticed a remark of Rob80b, that his fakes were sounding astonishingly close to the real IE800, barely distinguishable.
And indeed, I found mine sounding very well. I compared them with my Sony MDR-EX1000, which was the last non-BA flagship IEM from Sony and had got very good tests, also here in Head-Fi. My fake IE800 sounded quite similar, but in my view even a bit better. So we are definitively talking about high quality sound. But the question whether a real IE800 might sound even better, did nag me over the whole time, and so today I took a long journey to a Sennheiser dealer with IE800. The result absolutely stunned me! Trigger warning: true audiophiles may feel shocked or worse from what I have to say...
I found the real IE800 significantly worse than my fake. I'm aware, that I'm talking about one of the very best IEMs, and never would I claim to know it better than Sennheiser or others. But this does not change the fact, that for me the real IE800 sounded somewhat dull in comparison, much less desirable for myself, in a mixture of music genres. The salesman, quite young, did also a test, but he found the real IE800 better, finding my fake too bright. This may make sense, because at 67 my ears' frequency response is definitively weak in the highs. But this applies to listening to the EX1000 as well, and it also applied to my former listening to my HD 800, which I used for years until 3 months ago (so I can't any longer compare).
I feel no longer interested in a real IE800, regardless of the price, and my present worry is only, how I would be left if my fake should brake or get lost. Because I know, that there have been plenty of fake variants, I have no chance to get a reserve. For which I would pay again $200 in a heartbeat...
To cut a long story short: If you, tom159, find your fake sounding "amazing", then you may consider to just keep and enjoy it. Otherwise you run the risk of adding significant money and losing much subjektive pleasure!
The more subtle message behind my post: you won't automatically enter "audio nirvana" by shelling out the money for a real IE800...
Just my 2 cent...