I will have to disagree with the being caught aspect. IRC is the last thing that will get you caught.
And as far as getting virii/trojans.. it is far less likely to get one off IRC (assuming you use the larger warez channels). The larger channels will ruin their status and their users if they allow trojan/virii to be served. While IRC may be the most annoying and tedious way to find ILLEGAL files, it is also the "best".
But don't forgot, it is still ILLEGAL.