I am really happy with my Powerworks kit. I got 14 lbs of boost right out of the box and at just 2800 rpm, I get 9-10 lbs of boost. My car pulls so hard at lower rpms and you don't have to spin the crap out of the motor to get decent power. Also, one of the best things about the PW kit is the whine of the blower. It is so loud!
And as far as 1/4 mile times, I run consistant low 14's at 102-103 mph. And that is spinning down the 1st half of the track. I can't wait to get a LSD and slicks!
That's the differance, your 14lbs vrs my 13lbs. I've ran 13.4s at 12lbs. Now at 13lbs, last week in 90+ weather, I ran a 13.9 with a bad clutch and street tires. That's with a 2.4 60 ft time, and shifting between 6k and 6700 rpms depending on when it starts to slip, and no powershifting. It's not the amount of boost you have, it's how much air you can flow at a cool temp.
Like I said before, the Vortech H.O. is the way to go as far as superchargers on the SVT Focus. Hands down, nothing can touch it.
overall, any type of centrifigual charger is best. no matter what brand..theyre light years more efficient then a paxton or roots based system.
id go with vortech, just because of the experience i have with them, and also...air/water intercooler is a nice piece that makes a hell of a difference. Its more expensive yes...but you definitely get what you pay for in terms of power.. 270+ at the crank with a good tune. not bad for 8lbs of boost