Virtex or Stratix?help

Hi friends

I am working in a pvt concern.We are decided to purchase FPGA trainer
kit.
But we are confused with Xilinx-Virtex-5 and Altera-stratix-3.
Which one will be the better in configuration?
Feauture-wise which one will be better?
And which altera device has the feature of ML505 in Virtex-5?

Plz give up some ideas regarding thiz…

thanks