Well the stiffer the suspension, the less travel. Up to a point it improves handling, but after a point it decreases it. Depends on speed, how tight the corner is (lateral forces) and road conditinos. That's what racecar drivers spend so much time sorting out for each track.
For daily driving I wouldn't worry about it. You're not gonna run something that stiff like an all-out track setup. Not practical, plus you're not gonna put your car right on the edge of the performance envelope regularly either... at least i hope
Koni or KYB AGX shocks are very nice along with Eibach Pro Kit springs or H&R or even Neuspeed. I have Konis and Eibach. Great set up. There are usually group buys on them.
www.groupbuycenter.com
Lastly - read the FAQ section. There's a lot more info in there on this subject.