If you want roll resistance, install a big anti-sway bar. If you want a stiff ride, install big T-bars. The preceding is an exaggeration, but it gives you the basic idea. If you are building a track car, you want both. But for a street car built for regular driving, a moderate spring upgrade and a sway bar is a better package than stiff springs and no sway bar. My slant six convertible is running on stock springs with a Hellwig hollow front bar and KYB shocks, and it handles fine on twisty roads, considering its modest speed capability, and has great compliance for less-than-perfect road surfaces (which is pretty much everywhere in California). My SB fastback has .890 T-bars ("big block" size), HD rear springs, and front and rear sway bars -- this is much less T-bar than people are typically advocating, but the only reason I would go bigger is to reduce nose dive under braking (this was noticeable on the track). The funny thing is, on a typical mountain switchback, the convertible can actually get around quicker, simply because it has power steering -- the manual steering on the FB is just too slow. At high speeds the FB is more stable, but how fast can you go on public roads? Setting your street car up for optimal cornering at 100mph is kind of pointless, IMHO, unless you are just in it for bragging rights.
