standard front swaybar is about 16-18mm, on the front - there is none on the back
On my old ta22 - now sold - i swapped this for a 24mm front bar from Kmac , and a rear whiteline 18mm bar
both i put im myself - and im not a overlymechanical guy - so it was pretty easy
the cars rear end was 100% better handling wise - and front seemed to have a lot less understeer issues . It was also alot flatter thru bends
i was runing standard toyota springs at standard height , and monroe Gt gas Shockies all round
As an example - my ta22 was capable of keeping up with a Gt4 just about , in relativelky flat twisties ..
Budget wise - the whole setup cost me less than $600 to purchase parts + fit - IMHO the perfect entry level upgrade before looking at things like heavier rated springs , koni shockies etc