As an ex-AS-D2 owner I can confirm there is certainly no contest between them at this point in time

That said, the only thing they have in common is the fact they are both stainless steel razors, the design ethos is completely different... I'd say anyone that loves the Feather is likely to dislike the Rocca and vice versa. Perhaps if Muhle enjoyed the production budget of Feather then the Rocca would be a very different razor indeed

(Andreas Muller is on record saying all of the difficulties with this razor are due to their self imposed stipulation the RRP must be no more than 100 Euros.)
Speaking of the Feather,
@Grishnak, if you're looking for a mild stainless razor and you like the Tech then definitely check out the AS-D2, it's basically a stainless steel Tech.