Personally I have no problem with LS2... OK the later versions of LS3.5 have double the memory (16MB instead of but the actual quality of the sound is not much different. The sound files for the Roco BR18 are pretty convincing, you just don't get as many sounds as you do with for instance the PCM 01 - but what's there is fine. I think it'd be dangerous to assume that just because a model has a later version of Loksound it's going to be better... especially with earlier Trix/Maerklin models using the capability to add stuff like station announcements!