Howdy Everyone.

I was wondering if anybody had any insight on Malossi exhausts for the 2015 primavera/sprint.
There are two Malossi exhausts I'm looking at:

Malossi Racing Exhaust For Vespa Primavera and Sprint 150:

Malossi MHR Racing Exhaust for Vespa Primavera, Sprint 150

Does anyone know what the difference is with these? Should I get the Malossi Lambda emulator? Does anyone have one that can vouch for it?

My current set up is the stock engine, SIP cluster, Malossi Variator 13.5 gr rollers, Malossi clutch. I'll be adding the Malossi X-belt, new rollers, new Malossi variator fan (just came out) and Malossi airfilter next week.
I appreciate any recommendations or suggestions!