They dont all come with active LSD's it was an option and from my understanding it was an option for all R33's. Ive seen 95 models with active LSD's in them.
To answer your question its only minor cosmetic differences. A new front bar bonnet headlights etc. Interior trim is updated along with dual air bags standard. Motor only has minor differences to it but the turbo uses a nylon compressor wheel instead of a steel wheel. Exhaust wheel is still the ceramic type.
Hope this helps
Cheers
Chris