db move from solaris to aix

hi!

i want to move oracle 9.2.0.5.0 from solaris 9 to AIX (which is brand
new).
size is 150 gigs no rac,no replication,no standby.

i feel if i go with exp/imp its gone take a huge time for exp and
space issues for holding the .dmp file (any idea how much will be the
size of the .dmp file for 150 gigs and estimating the time)

is there any other possible or do u think exp/imp is the good choice
to go ahead.

any exact procedure. step by step .

thanks

.