audio system needed

hi all.. am new to this forum, i've got a NISSAN MAXIMA '03, which is the same as INFINITI I35 in US, and everywhere else... in the gulf its called NISSAN MAXIMA.. anyways, i have two head units to choose from, one is SONY CDX-R3300, and the other one is CLARION DB346MP.. i dont know which one would be better... i was thinking to install the CLARION one, since they told me, that my car originally got CLARION speakers.. i dont know what to do...
any help?

thanks...