In that case you can combine it with rtcontrol (you will need SSH access though) and you will have some pretty awesome results. Been there, done that ;)
You can set rtcontrol to stop all torrents bigger than X size so even if RSS starts downloading a huge torrent, rtcontrol will stop it. For example, you can add this line in crontab and run it every minute:
Code:
rtcontrol is_complete=no is_open=yes size=+500m --stop
In this example, your RSS will start downloading all new torrents but rtcontrol will run every minute and stop all those which are above 500 MB so that you don't screw your ratio with huge torrents :)
For more info, have a look here: RtControlExamples - pyroscope - Real-world use-cases for rtcontrol. - Python Torrent Tools - Google Project Hosting