SONY XS-L1035 in ported?


Hi
I'm not really new to speaker building but I'm not expert either.. I have one question that's been on my mind for ages now:
I'm considering purchasing a sony xs-l1035 sub, not for a car but for my home setup.. the question is, why does everyone say it sound crap in a ported box? Its recommended for the sub to be run in a sealed box but i'm after low end bass (from around 30hz onwards). The thielle/small specs of the sony inputted into WinISD suggest a flat response in a ported 60 litre box to 30hz, with an F3 of around 25hz..
The theoretical response sounds mouth wattering (for me) when compared to my current RadioShack 8 inch..
I really don't see why this sub shouldn't be used in a ported setup..
could it be the group delay (34ms at 22hz)? the amp i'm using now is only 50 watts.. i will be planning on making a 150 watt soon though.. I also have a 20hz highpass filter for protection...
can anyone tell me why this speaker is unsuitable for ported enclosures??


Follow Ups: