Thank you all for your answers. You have been very kind and helpful. I absolutely love this thread. Have read the last 300 pages, in the last month, would love to have the time to read more but it is almost an impossible task.
It is already very, very hard to test any quality gear in my Country / city, let alone niche brands like Grado. Plus the models I'm interested the most (limited editions, Professional or the latest releases) are not sold by Companies like Amazon here in the EU, so unless there is some issue with the unit, a "trial" period is rare to be given, especially in these price ranges. I have to rely on your experience, feelings and thoughts to make my decision based on my best gut feeling.
I took a gamble with the Hemp. Without any decent comparison unit or experience, I could only rely on my ears to understand if I liked what I was listening. And so I did, but thought that it was related to the audio quality improvement over the low quality I was used to. Then I got the even expense Campfire Holocene IEM (I bought it at half the retail price) and realized that it was not the case since I was listening to a good quality unit, more technical than the HEMP but without giving me the same emotions. So, my gut feeling regarding the Hemp was right after all. I guess just pure luck!
Now, having the Hemp as my reference, I take special attention to the comparisons to other models and from what I understood until now, the GH2 is a better Hemp version but, IMO, no enough or maybe to close to justify a 700€ investment. The P500e seems more like a side leap instead of a forward one, unless you value bass the most. Again, something too close to the Hemp to justify the investment. The P2000e seems really special but totally out of my budget new and used is still expensive and the lack of warranty scares me (see reason below).
All the older units (mostly on the used market), especially the e versions, kind of "scares" me for 2 reasons. First because in case of issues with it no more warranty and in all honesty I don't think there is even a Grado representation in my Country where to send it to. Second because the lack of bass, compared to the hemp and X line, kind of puzzles me if I would like the signature sound.
I am really curious about the RX1 and RX2, maybe even more the RX2 but once again I fear if the leap from the Hemp is clear enough to justify the purchase? It is not clear to me in the case of these models. Also it is my understanding that in terms of bass the RX1 is the one that resembles more to the old Grado sound.
Finally it comes down to the new 1000x and 3000x. Despite being curious about the 1000x, it is the one least discussed here and cannot find much information about it. So not sure where it stands. Plus, for just more 500€ we are in the 3000x domain where all reviews and opinions seem to be stellar and gives the idea that, despite not being cheap, it delivers above its price range. I honestly got excited by all of your "reviews" but a blind 2000€ investment is not something to be taken lightly (at least for me) and that is why it created me natural doubts if I shouldn't go a little "lower" in my expectations and "gamble" with something a little cheaper.
Sorry about the rumble but this new hobby of mine is sure not a cheap one and even worse, a guessing one in my case most of the time. I really envy all those of you that are able to test or try gear before deciding. That would make my life much simpler for sure!