it won't change the look at all - no height difference. Just adds more lateral stability to the handling - ie, controls the roll of the car through cornering, helping to keep the maximum tread face on the road to maintain grip. You don't HAVE to do front and rear - but you'll find that you'll either have an increase in oversteer or understeer if you only do one (depending which one you do)
further to what tinny has said, the larger the sway bar the more stiffness.... but bigger isnt always better. for instance, installing a bigger/stiffer sway bar to the rear will tighten things up back there, but this will also promote more oversteer to the front... so going too big will make overall handling even worse with the tail constantly losing traction. sounds fun, but really it isnt- especially when the rear end pops out when you dont want it to. so then you'll be tempted to put on a bigger sway bar to the front to balance things out a little more.... problem solved? no. then you have too much stiffness overall, and any bump or rough surface on the road as you go around a corner will get the car all upset and you'll lose handling once more.
unless you are setting up specifically for the track (nice smooth tarmac) dont go too big or you'll stuff up handling. factory settings for most production cars (not sport orientated) are naturally set to understeer. understeer is much easier to correct for the novice, and the car behaves more predictably by simply heading in the same direction when you turn the wheel. but there is certainly more to be had from the VE stock setup.... if you know what you want from your car and what your abilities are.
my suggestion (if you havent done it already), is to go to a skid pan day with your car. get a great idea on how it behaves at its limits (and how you behave too!) and then decide what you want. my thinking is you should go for an upgrade to the rear sway bar only and see how that goes (not too big because then the front will need doing too to compensate). while youre at it, get some new bushes too (plastic 'washers' that join the suspension bits together- crude explanation) because stock ones are soft rubber (for driving comfort) but newer ones are made of plastic (or go half half with rubber and plastic) which GREATLY sharpens up your handling response. everything will feel tighter and youll get more 'feel' from the road... but then comfort takes a small drop down too with more vibrations felt through the wheel (driven a go kart before? an exageration but that vibrating can make for tired sore hands so again... not too hard).
long story short.... strut braces are for wank factor only, unless specifically set up as part of a tuned suspension setup. most people who install them dont know what they are doing.... they either put them on too tight or too loose, affecting suspension geometry and making things worse! (oh well, least it looks good right
). plus, its the LAST thing I'd spend money on for a late model car with superior torsional rigidity anyway! very little body flex these days, and even the small amount there is wouldnt be noticed until you completely upgrade the rest of the suspension anyway! if you have any other stock parts, strut braces will do jackall.
springs, then swaybars, then bushes, then shocks, then coilovers (to upgrade springs and shocks previously installed), THEN.... after coilovers... strut braces and roll cage to tighten up the body. until then, spend your money on other crap
. strut braces are the cherry on top of thousands of dollars spent already on suspension.... not the starting bit.
