I'm actually pretty good. No remorse with my Mazda or the 2014 Escape. With our 2013 Explorer, I wish I would have held out for a Limited with sunroof & NAV . . . but I won't have that problem here. The differences, as you stated, are the design and engine / chassis. At this point, I don't know enough about either to have a preference . .
I've always enjoyed the idea of modding cars, but I've never been one too dive too deep into it. My Speed6 was the furthest and that was an SRI, upgraded fuel pump internals, upgraded engine mounts, wheels/tires, badging and coilovers.
Yeah, that part is crazy - I've been in the "cult following" for a car before with the Mazdaspeed. The Speed6 was a beautiful car (in my opinion) and there was a rather large Mazdaspeed forum (supporting the Speed3/Speed6 and even the CX-7) that I used to frequent. Prices were never really affected by the rarity / following though.
I have looked into warranties - specifically I got a quote from the 3rd Edge I shared. They quoted me $1,995 for a 3-year / 36,000 mile bumper-to-bumper warranty with a $50 deductible, which doesn't seem terrible.