Hi @franx
I own an L2000 tribute, I would say that I love the bass and the sound versatility (balance, active/passive, active amp, parallel/series).
Personally, I was thinking about getting the American version, went to the store, tried the American and tribute version, and end buying the Tribute.
One thing you want to consider (depending on your hands) is that the neck is really thick and some G&L seems to have a neck wood issue, and in some Tribute, frets aren’t leveled and G&L doesn’t seem to have the best customer service (I can’t attest to it, but you can find a lot of info on that regard in their forum).
That being said and if you check on those things, I think it is a wonderful and reaaaally versatile bass.
If you are good with electronics and you want to, there are also schematics on their forum to make some changes on the control circuit to expand the control possibilities even further.
Can’t say much about a Fender J-Bass but there are standards for a lot of bass players around the globe.
Imho, you can’t go wrong with any of those.
They have totally different sounds but are top-notch, so it’s a matter of personal preference.
Just go with the sound (and looks) that you like more.