hahaha.. like henry said, stability in the corner has got to do
with a lot of other factors... assuming you're using a properly
designed and constructed, and ASSEMBLED single-sided swing arm, no
difference from the dual-armed types... perhaps i should have added
the 
icon to my previous posts... 
just to name a few bike specific factors for stability in corners:
fork rake angle, tire profile/surface/temp/pressure,
preload/compression/rebound, frame rigidity, damper or no damper,
lean angle, rider's actions as a whole... the one or two side swing
arm doesn't play a part here lar... i got a friend who can bua ka
tar on the right corner, but just not left... really it's up to the
rider...
as for single sided swing-arms allowing for better shocks to be
used.. i mean.. er... huh? 
how?? anyway, a suzuki TL uses its custom-made rotary rear shock on
its DUAL-sided swing-arm... 
anyway, single sided swing-arms help in terms of weight (usually
lightweight/hi-strength alloys) and ease of maintenance like
changing of tires, adjustments etc... the most important thing is
that it is properly assembled back whenever the wheel comes off.
mechanics who know what they're doing use torque wrenches for
securing the wheel. a torque wrench allows you to set the torque on
the nut when tightening. torque settings are important because the
nut can't be too loose or tight for obvious reasons esp when the
wheel is mounted on one side only... hence my emphasis on the
proper use of tools.
ah.. single or not single still a bike... i love my dual swing-arm
planet...
