They dont make the A-trim anymore. They make the SC-trim(what I have). I voted for the Paxton. Please listen to me and get the paxton. Seriously, unless you have big big plans(over 15psi) their is no reason to get the Vortech.
Both blowers are dead even, maxing out at around 15psi (despite what Vortech claims on thier site). Actually, the NOVI will spin a little higher RPM than the SC so its a tad bit better head unit. In addition, there are several reasons why the NOVI 1000 kit is superior to the Vortech kit. See thread.