First off, let me start by saying that there are only a few (like five) major battery manufacturers in the US, and you have a VERY good chance of buying the same battery with just different store brand label... Very common to buy generic consumer batteries and private label them. (I did.)
Two, you would be better off learning how to read the manufacturers marks and date codes than worrying about Cry Hard or Wally-World labels. (probably made in the same plant, on the same line, just different labels)
Learn Date Codes! This way you know how long that battery has been on Auto-Mart's shelf before you ambled in there looking for one...
Setting on a shelf, partially discharged is HARD on the Lead Paste the plates are made of.
I remember the 'Interstate' and 'Die Hard' wars about 15 years ago...
Both were made in the same plant! Just different colored cases!
Outside dimensions are determined by the B.C.I. or Battery Council International.
For instance, all 24 series batteries will have the same outside dimensions, same tie down lugs (if applicable), same post locations and same polarity of posts...
For example, a 24 is the small top post battery, much like the one in the picture.
A 24F would have the polarity reversed (positive terminal on the other end of the battery) for Ford applications.
Same with the 27 and the 27F... ect.
If you REALLY want to know how heavy duty a battery is...
Weigh it. Nothing more than that.
The heavier a battery of any BCI size is, the more lead there is, and normally the more potent it will be.
The battery plates are eaten away in the electrochemical process, so the larger and stronger the plates, the longer the battery will last.
Lead is much heavier than case material or electrolyte, so you can normally tell pretty quickly if you have a light duty or heavy duty battery for any given BCI size.
You may also want to squeeze the sides of a few batteries (or end to end to be more precise).
This will tell you pretty quickly if the case is thin skinned, or heavy duty...
This isn't a real problem in the average grocery getter, but in a trail rig...
Build a strong battery tray (IE: NOT a factory CJ Jeep tray) and this shouldn't be a problem for all but rock crawlers and Baja racers.
Shock loading from racing is notorious for beating the plates loose in batteries.