Well, I decided to go physically look at all of the items mentioned here. The Justrite was tempting, but the foldable funnel seemed way too cheap and the can itself seemed a bit clumsy to handle, therefore was ruled out. I almost pulled the trigger on a No-Spill, and even though there was a clear difference, it reminded me way too much of what I hate. So personal bias ruled it out (although I may look their way if I need another in the future). So then it was down to the Sure Can or the Eagle. The Sure Can really looked clever, and was well thought out. The Eagle was all metal (except the handle, but if it ever breaks, I can replace it with a metal handle), and the funnel seemed like a decent design. The Sure Can seemed like the spout would leak over time, especially being bent at different angles (especially the awkward twist to lock it into the upright storage position), but seemed much easier to fill. The Eagle seemed difficult to fill, and unfortunately had a non-removable screen/flame arrester, but was cheaper.
The Eagle emerged victorious.
And wait, there was a second winner. The EZ-Pour kit came home with me too.
The price I paid for each was stellar also. My local Atwoods had the EZ-Pour spouts marked for $7.99, and that's what they rang up for. They strangely automatically applied a 10% discount (on the receipt), and it rang up for $6.99. Even says "10% purchase $0.70 discount" on the receipt. Not sure how that math works, but works for me! And the Eagle can was on sale at Tractor Supply for 15% off of $39.99, so I went to Lowe's and had them price match so i could burn out my gift card. So grand total for both was under $40 (tax exempt). Happy camper here.
My only gripe is with the flame arrester on the Eagle. I wish it was removable so that if junk gets in there, I can remove it to clean it. Because whatever junk it catches while pouring into the can will exit when pouring out of the can.
Thanks for all the input. Hopefully no more spilled gas is in my future...