Which router to buy for the Zone Based Firewall

[juno_q_beat]

Hi people

I am planning to sell my 26xxXM routers and get something better to run IOS 15x for new CCIE

I am wondering if someone can sagest me router that will be good to use as Zone Based Firewall .

I am thinking of 1841 with min 256 Dram, that should be fine I thing

Many thanks in advance

[Leo Laohoo]

How big is your bandwidth (present and future)?