We replaced the battery in my wife's '69 C3 shortly (w/ in a a year or so) of when she bought it in '06. It was an AutoZone 75 series (same size as or Zs batteries) and it has been maintained with a BATTERY TENDER whenever it was parked in the garage. It still cranks her 11:1 compression SBC over "like new".
(Flooded) Lead-acid battery technology for cars use has been pretty stable for 100+ years. So, for a given series size battery, they generally perform comparatively the same, more or less. But, the KEY to long life is how they're maintained!
Long story short, a chemical reaction between the sulfuric acid and the lead plates will occur to form an insulating barrier coating the lead plates - effectively reducing the area of the plates to the electrolyte which has the effect of reducing the battery's capacity (thnk:
size) That's the bad news.
The good news is a charging voltage applied reversing the internal discharge current flow direction has the added effect of arresting the formation of lead sulfide crystals and removing the crystals from the plates which falls to the bottom of the battery (along with a slight but important amount of free lead material).
So, putting a "trickle" charger on the battery when not in use keeps the formation of lead sulfide at bay, but
once the battery is fully charged (especially), then hydrogen molecules are stripped from the electrolyte (H2SO4) and water molecules (H2O) commonly referred to as "gassing". That's not so good for several reasons.
But, technology to the rescue! IIRC from research (decades ago), it was
Texas Instrument that developed a chip that would monitor and trickle charge a (car) battery until it reached full charge, and then switch automatically to a "pulse" mode which would stave off the formation of sulfide w/o causing the "gassing" which was the issue with previous (aka "dumb") charger/charging technique.
Nowa dayz, practically all the better chargers have "TI's" technology on board, including "TI's" Battery Tender which is what maintains Ami's AutoZone battery for around 12(?) years now.
Worth mentioning... Our cars draw a tiny amount of current necessary to support the radio pre-sets and the stored history and learned performance data in the ECM. So, disconnecting either one of the battery cables or employing a manual battery disconnect switch, will prevent the current from trickling away while the battery is not being charged. Coupled with cold (or especially freezing cold) temps, the chemical reaction resulting in the sulfide formation is significantly slowed as well.
So, coupled with ample reserve capacity of a relatively fresh series 75 battery, some prefer to installing a battery switch to using one of the battery maintaining (pulse type) chargers - especially in unattended locations or locations w/o a power source.
Which method is "best"? Well, technically, the modern "pulse" type maintainer provides the standard by which the battery cutoff switch technique is judged. However, practically speaking, there may not be any significant difference,
depending on the conditions under which the battery is stored.
So, for the cost of a fill-up or two, you can buy a (pulse) type charger. Is a few more years of good service worth the hassle compared to a cutoff switch? You'll have to make the call*.
*Note: My (decade+ old) data stems entirely from that of standard flooded, lead-acid tech, and may or may not directly apply to other lead/sulfuric acid configurations, e.g., AGM. So, YMMV, as they say!