Originally Posted by grizz1

The 0801 is basically a top end pipe with a long header, so gives good performance all around. It is a pretty thin walled pipe (the GO version), which dented very easily and the stinger was subject to damage.
More recently there has been other 0801 pipes produced like the APlus 0801, which is a much stronger pipe.

The 2072 is the later model. It has a large volume chamber, slightly bigger internal outlet size on the stinger.
It too has the long header and gives wicked bottom end power as well as strong mid and top end performance. Very strong and durable pipe.

For the GX motors I would recommend the 2072. The GX motors were developed around using this pipe, so it has the best performance characteristics on all three GX models (as far as GO pipes are concerned) IMO. It is a very nice pipe.