Hi All,
Figured I'd add my experience here and try to summarize my findings after I spent the last 10 days or so doing a bunch of research and comparisons. My interstate OEM-style (27F) battery starting giving me trouble and ended up completely dying shortly thereafter right at about the 3 year mark a month ago. (shout out to Mudrak who replaced this for free for me when my vehicle was in his shop in Sonoma, CA getting suspension and E-Lockers done back in Dec. 2018!)
TL;DR: I went with Advanced H8-AGM, Brand: DieHard which is same price ($210 after $22 Core, $200 out the door with 10% military discount), stats and manufacturer as Autozone H8-AGM (Duralast). It drops in to my 1999 LX470 perfectly, being approximately 1" wider to each side, but the bottom has a form so it locks in the OEM battery tray despite the overall battery being a little wider. I then cut a 6.75" x 3.5" x 0.5" (thick) piece of wood from scraps I had lying around to sit on top of the battery as a spacer for the OEM bracket to go over and hold it down, as this battery is a little shorter than the OEM one. All is good now with way more CA, CCA, reserve, etc... as others have mentioned over stock.
More in depth notes: I ended up shopping a local Interstate, the Toyota dealer, Advanced, Autozone, and O'reillys (Roanoke, VA).
Toyota wanted $180 for the OEM Truestart brand. Interstate wants $165 for their OEM battery with the same stats as the Toyota Truestart. Some of the other big names had the OEM 27F in stock and some did not across 2-3 stores of each in the general area. Their pricing is all over the board as well for the different levels of batteries they have that match OEM, with most of them having the same exact stats for CCA, CA, etc, although there is some variation in the regular/silver, gold, platinum versions along with the different warranties.
I went with Advance because they were the only place close that had the H8-AGM in stock, and I wanted the H8-AGM battery based on reviews, IF I could find it. As noted the batteries from Advance and Autozone are the exact same price, and stats. I couldnt find information on the manufacturer of the O'Reilly's H8-AGM battery, however the price and stats on that one are the same as the other two as well. They told me they couldn't even order one and get it here in a reasonable timeframe like they usually can all other parts which I thought was odd. Warranty is the same from all three manufacturers as well.
My local Walmart did not have the OEM or AGM batteries in stock, so I didnt look in to them much further. I didn't shop Napa or the wholesale places at all because I dont have memberships to wholesale clubs, and honestly I was pretty over it at this point, so just went with the closest place that had the H8-AGM.
This got long, but I hope it helps someone out there. On Paper the H8-AGM should be one of the best batteries without getting into the $300+ range. I guess time will tell. Will try to post back if I end up with a bad experience, but if I get another 3 years I'm happy with that. The 100 has 4 circuits of extra lights (and counting), a winch, and a fridge that stays plugged in almost 100% of the time. If not for those things I would have stuck with stock Toyota/Interstate.