I havent played Mario Kart since my brothers moved on and I havent had anyone to play them with : p (Also I could not find Double Dash at all ever, I tried to find it too)
I always really liked MK64, though. Even playing it alone was fun for me, I liked the simple and pretty racer game it was. My favorite was always the battle mode though : p Even my older sister and her friends would play that with us on occasion, and she was like an older teen when I was still a kid so that was pretty cool : p
I like Diddy Kong Racing more though : p Wish Rare continued with that one.
EDIT cuz dont wanna keep double posting-
Nobody here will probably agree, but the only Mario Kart games I ever loved were the original three. I prefer the classic pipe-frame go karts and the tight, clean, basic roster. I hate filling up games with too many random or guest characters. The general flavour and style the series went in (starting with Double Dash) is just not my bag.
Mario Kart 64 and Goldeneye were undoubtedly the two most popular multiplayer games of the N64 era. Insanely popular and highly influential within their respective genres. And yet, due to their antiquity today, both of them are considered "unplayable" by many kart racing/shooter fans.
I have played Double Dash with CMV a few years back, and while Id agree that I liked the simple versions on SNES and N64 Id say that I really liked DD too : p It was cute and simple too, with just the pairing thing being added.
And for the Goldeneye and MK64 thing, thats all just a technology thing. Like alot of old NES games would be thought of as "unplayable" by many of todays gamers, but that doesnt mean theyre "bad", at the time they were amazing games, but these newer gamers started with titles released AFTER those games, so now to them those games seem rougher.
I have seen this often with people who started off on their love for LOZ with Twilight Princess, like every single one of them that I have met hates OoT even though when you break it down its like an OoT remake but wolf : p