I got the Infy Pr9603iS finally after much consideration. Got them for 2.9 something off eBay so immense VFM
Skipped the reference because :-
*Large price differentials. (2.9 vs 3.6)
*There's a passive crossover on the Refs but I could hear no perceivable difference
*Same drivers on both and the tiltable tweeters were not a criteria for me.
*Refs look better but in a silver Santro the primus went well.
I could have got the Pio's but didn't as the primus were a steal.
I advise against using ANY 2 Ohm speakers directly with the HU. You're asking for trouble!