Being an old Suzuki driver for the last 20 years, I would have no qualms about picking up a used SX4, that had been properly maintained.
I have the 2009 model and I would have to assume that the 2007 would be very similar.
I would verify just one thing though, that the timing belt is of the "Lifetime" variety.
I just got out of a 2006 Forenza and it required that the timing belt be adjusted by a Suzuki mechanic every so many thousand miles. At $140 per, that can get real pricey if you're a high mileage driver. (and I am! )
My 2009 SX4 DOES have the lifetime timing belt, requiring NO readjusting at regular intervals.
I have had three NEW Suzukis now.... a 2000 Grand Vitara, a 2006 Forenza Sedan and now the 2009 SX4, basic, without GPS, Cruise Control, etc.
I love my little SX4 ! It's easy to drive, easy to park, turns on a dime and rides smooth and quiet. And, if you need to get into a high speed Interstate with a short entry ramp, the SX4 is up to the job.
Navigating through high speed traffic is a snap for the SX4.
This little SX4, pulls every bit as hard as my 2000 Grand Vitara with the V6 engine, and gives me better gas mileage.
Having had 4WD's in the past, with Warn Hubs, I got really sick of having to get out of the vehicle and lock in the hubs to use the 4WD function.
In the SX4 that's nothing more complicated than activating the 4WD rocker switch on the console. Living out in the country, on sand roads, I use the 4WD feature a lot.
I won't risk my warranty, by telling you all the things my SX4 can do and has already done.
As with even a brand new car, give it a test drive before you buy.
Good Luck and Happy New Year!