if it me i definately opt for a matrix.
since its a new car u dun hafta worry abt break down and stuff but
if its a 5yrs old car and above i'll go for toyota.
with the matrix u dun compromise on space and comfort but on vios u
hafta do that. fuel comsumpution would be slightly better on the
vios as its a 1.5vvti compared to hyundai 1.6NA engine.
another consideration is u might wanna check out hyundai matrix
revo 1.8 auto. its exactly the same as the matrix 1.6GLS but much
more powerfull. actually matrix with sports kit (window visor, side
skirting,fog lamps, rear tinted glass,sun visor, rear spoiler) will
make it look like a SUV leh... very nice 
btw u damn lucky arh... pass only get to buy new car. your parents
paying for it or wat?