Hi Malandros, welcome to the Forum 8) . Hey, we?re suddenly getting a lot of guys from Spain now, well 2 or 3 of you at least!
OK, afaik ??all? MIJ Tokais should have a serial number, but the MIK models did not have serial numbers until about 2000 (I?m guessing approx. date/year). So if doesn?t have an S/N then expect it to be MIK almost for sure. As Novosel says ? MIK Love Rocks have white control covers & 3 screws in truss cover (whereas MIJ have black covers & 2 screws in trc).
Yes MIK can make a big difference, because some models such as LS48 had plywood body! Though I'm not sure if that still applies to current MIK models. In contrast, all Japanese Love Rocks had/have solid Mahogany back & solid maple top, although those with highly flamed tops are usualy veneer glued onto the maple top (except on expensive models like LS200). Some cheaper models may also have photo-flame top, but again I think that applies mainly to MIK models.
Take a look in the Registry at the Catalogues, that will give you an idea of the specification for different MIJ and MIK models. Price depends entirely on model number (for new guitars), eg LS50 is cheaper than LS70, and LS200 is much more expensive.
As far as tone quality & playing feel is concerned, well that?s very subjective & everyone has their own individual view. Some guys here like the MIK guitars, but some don?t. Try a search for ?MIK? and you?ll find lots of discussion about it (seach also for "LS48" - interesting debate here about that guitar). If you search enough here, you?ll find I keep recommending old MIJ models, but that?s just my own preference of course :-? .
Ian.