So far, no one is arguing. If you're looking for someone to powder you butt, tell you a bedtime story and tuck you in, that ain't gonna happen. If you're lookin for good advice, you've come to the right place.
So here's the skinny about Champion and ANY other "bargain" type radiators. They're a crap shoot. Most of them do pretty good. But they do have a fairly high rate of ill fitting, don't cool worth crap or just don't fit at all, so be warned. Having said that, I have one in my 64 Valiant. It cools GREAT. The fit could certainly be better. I didn't have to modify anything, it just fits VERY tight, because the side brackets are welded in in such a way that they position the core closer to the engine than they should and that takes away valuable space A bodies need. Especially early A bodies. But yeah, if you get a Champion, or any other import radiator, you'll likely get one that'll work. The odds are in your favor.
Since you're looking for something that's an "easy drop in solution that won’t have to trialed and errored and sent back", your words, I'd NOT look at a 26" radiator. That Be Cool unit, while more pricey will cool a Sherman Tank with two rows of big tubes. That's about as optimal design as you can get.
Lastly, before you ASSUME someone is talking about YOU, read and comprehend what they wrote. I have no problem pointing YOU if I mean to. I did not. I said "some of these guys" or some such, which does not indicate YOU, because you have not proven you're not listening. Yet. If you're looking for a more concrete answer than I've given about import radiators, you won't get one and if you do, it will be incorrect. The best anyone can offer is "Yeah, they'll "probably" work good", as most do, just remember that word "MOST". Good luck with your choice.