Single or Dual batteries for Bafang BBSHD?

I'm likely to be getting an BBSHD in the near future, but was kind of wondering if a dual battery (2x24v) would provide any real benefits?

Skip the 2 24v battery thing and get one of these, with a 52v battery you'll get a bit more top end with the BBSHD. I have a couple of these batteries and get good range 20-30 miles off of one at a time, I pedal a lot too and can ride for a couple hours usually on the 13.5 amp hour battery. Your range you get will of course depend on hills, how much you pedal, total amount of weight you are carrying, headwinds, etc.

https://www.empoweredcycles.com/collections/batteries/products/52-volt-58-8-volt-fully-charged-13-5-ah-sanyo-ga-hailong-1

(I see he's sold out of batteries currently but should get more soon, good batteries with genuine GA cells, fair price, based in S.F. Bay Area, fast prompt shipping)

2 X 7S batteries in series is the same as "52V" (14S). So in that case, I'd choose by desired total capacity/whatever packages the best on your bike.

I bought a Diamondback Recoil 29 (https://www.diamondback.com/recoil-49966) a few years ago and only recently decided to convert it to an e-bike using the BBSHD kit. I was leaning towards dual batteries simply because I would put them in a top tube bag like this one - Additive V2 (http://www.additive-bikes.com/de/ADDITIVE-BAG-V2.html) for better weight balance I suppose.

I also thought about mounting it on the bottom tube in reverse but I'm not sure if theres enough room to fit.