I think one of the problems is that once people buy a map they are unlikely to get a different map. Therefore they can't make the comparison that is required.
I guess you mean likely here....... 
I thought it is a parameter question only, therefore UN-likely to be different so comparable.....who knows the details here....I'd be quite interested... 
I do not see how my ABT would be better than a REVO or APR etc etc.....the big price difference (twice the amount) I translated that (so far) in warantee-matters...
You raise a good question. Ultimately the tuners are all given the same hardware with the same headroom. But its like giving different chefs the same ingredients. They will all serve it in their own way.
From what I have surmised Superchips (Bluefin included) seem to be quite conservative. Looking at their quoted figures (and the matching results from Rolling Roads) indicates they go for a lower horsepower and torque figure. IIRC then around 250-255 seems to be their ball park. Perhaps one of the reasons for this is that they want to retain the OEM drive of the car and so provide a gentle and subtle increase.
Revo seem to be inclined to give a little more torque. Although I am yet to see another Revo car match what Revo quote (FroGTI seems to be the only one). Revo quote around 275 hp and 310 lbsft torque but most I have seen (even Edition 30's) get around 268 hp and 290lbsft torque.
I have no experience or knowledge with ABT or APR and so cannot comment on either.
Personally I looked at Revo as I was drawn to their higher figures (sometimes you can't help it). But I ended up getting Graham from torque.it to do my car. He quoted my around 260-270 depending on the rolling road and about the same in torque. My car was tested with 270 hp and 289lbsft of torque which I was pleasantly surprised with. *My car was tested with Sainsbury's 97 octane Super Unleaded fuel if anyone wants to know.
Some tuners like superchips have provided a more OEM driving car whilst Revo are what I like to call "talk and torque happy". Although the same hardware, it is the delivery that differs.
And another reason I don't like Revo is that everyone I have spoken to with Revo has a flat spot they notice. Mine doesn't

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