I don't own a rat myself, not yet anyway ;-) but I know people who do and have seen enough demos of it to realise that your question is bit of an unfair comparison.
The Rats are far more versatile than a single jig. The number of joints which can be produced with the rats is astounding, my favourite is the dovetailed mitre joint, still cant get my head around it but it looks superb. However I understand the learning curve can be quite steep.
If you only want to do morticising buy a dedicated morticser, however you'll still need some method of creating your tennons as the morticer wont, this is where the Leigh or Trend M&T jigs come in. If you want a versatile machine capable of creating many different types of joints, buy a rat.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.