KG, did you feel your pants-leg being pulled a little bit there?
TAP isn't a reliable source for performance data. Lots of errors there. The "official" data from Cessna's Owner's Manuals (which is uncertified but useful) says the 170A has 592 s.m range at 6000 feet. It states the B model has 596 sm at 5000' and 629 sm at 7500', interpolation giving us about 605 sm at 6000'. All these figures are using 2400 rpm, and are without allowance for wind or fuel reserves.
The straight 170 has about 5 gals less useable fuel than the A/B models, (and therefore about 60 sm less range) but otherwise has similar performance to the A. (It should be said that it's a common modification for straight 170 owners to add a second tank to their left wing, to match the right wing installation. In such case, the airplane actually gains 12.5 gals, and therefore would have about an hour's more endurance than either the A or the B models.)
In reality, there's no "apples to apples" comparisons out there. No two airplanes are actually "identical, except for fight/engine times, and condition." Therefore each airplane evaluation must be made seperate and alone. But in theory at least, we try to subjectively "level the playing field" so that we can assign a relative value to each airframe, then decide which is the best "buy". Right?
Well, I'd say that the entire Cessna 170 lineup is a good choice for an "all around" airplane, regardless of which specific model is selected. All of them, under standard conditions, will carry 4 people about 3.5 hours w/reserve, burning about 8 gph, at about 120 mph, out of 2,000-2500' runways. They all have baggage compartments which can be used for any available unused useful load (generally placarded to 120 lbs.)
If those criteria meet your mission profiles, then the "best" one will be the one in the best conditon relative to price. The earlier models will likely carry a price advantage because most people do not place added value on the fabric wing. The A/B models, being an all-metal wing, is considered by most to have slightly more value due to it's ability to better withstand the rigors of outside storage, (although a fabric wing can be easily inspected/re-newed for internal structure etc., while the metal wing is a bit more troublesome/expensive if repairs are necessary, due to such things as corrosion. Fabric "skin" is simpler to remove/replace.)
The A model set the standard for the subsequent airplanes, and only minor "improvements" followed. Most "improvements" were in cosmetics, although some airframe design changes occurred such as already noted, the B-model introduced larger flaps and dihedral (for added stability although none of the earlier models had any stability issues), and the '53 and later B's had pressure cooling cowls and better cabin heating/ventilation. (My own opinion considers the still-later models with external tailwheel steering, serial 26505 and subsequent, an unnecessary and potentially troublesome complication, and I don't care for the '56 model's plastic interior, but otherwise they are good B-models.)
Buy the airplane in the best overall condition, with the lowest engine time, and the best avionics. All of 'em are just fine airplanes. IMHO (although there is anecdotal evidence that owner's of red B models are admired by more women.)
) to 689sm (599nm) at 2100 RPM at 7500 ft (5.0 gph). These are extremes. I use 4 hours and 100 knots TAS for planning purposes. Four hours chock to chock will use about 30 gallons. Your mileage may vary. 
