I designed the Beta 50s. They are an example of "classic" American floorstanders with lots of bass capability. In the large 4pi Harman chamber these speakers measure ~50Hz to 1000Hz + or -1.5dB. They dip a bit through the entire 1000Hz through 10000Hz region then come back around +1.5 dB above 10000Hz. The dip at around 3500 Hz hits maximum of -2dB. So in essence what you have is a classic but very mild Fletch-Munson loudness curve. Yet they still mesure very, flat overall. The 50s can be honestly spec'ed at approximately + or - 2 dB, 40Hz to 20000Hz. (I'm writing this from memory.)
Having said that I would caution that you should have a fairly large room and be able to position the speakers well out into the room. If this is not the case, the Fletcher-Munson "smiley curve" will be exaggerated on the bass end. This is not a bad thing as it is known that the vast majority of people prefer this type of warm sound over the "absolutely flat in the room" sound. The Beta 50s are also quite efficient so they take little power to get them up to a satisfying listening level.
I can't comment on the Paradigm's because they were not considered to be competition within the retail structure that Harman uses (by Harman Sales and Marketing) either in the US or in Europe. I therefore have not tested them. I can tell you that, like the vast majority of Canadian designed speakers the Paradigms' design is heavily influenced by the goverment sponsored Canadian Reasearch Council facilities which were originally set up by Dr. Floyd Toole who has been the V.P. of Engineering for Harman since the early ninties.
I would suggest listening to both, if possible, following the sighted listening regimen I set out in "Speakers: When is Good Enough, Enough" Part 2. What you like is the most important determining factor.
