I'm not saying they're exactly the same. I'm just saying they're both proven technologies at this point.
I remember a friend of mine had a wireless mouse back in 2003, and it was total shit. It was constantly losing signal while he was gaming, and he got so angry that he ended up throwing it across the room and destroying it. I would have never bought a wireless mouse at that point in time, but it's been 10 years since then, and the technology has greatly improved.
The same thing goes for SLI and Crossfire. The technology back then was new and had tons of issues, but any issues you might have now are pretty minimal and are usually easily fixed. I've personally never had a problem with either SLI or Crossfire either.
I'm not saying it's an exact comparison, but both technologies have been out for quite a while, and if there are any issues or bugs then they're pretty minimal.
You have to remember too, I'm 24, so I grew up with older hardware and operating systems than a lot of the other users on the site. Things were a lot more glitchy back then. I mean, I was on an old gateway back in 2000 that had a 700mhz Celeron processor that was supposed to be comparable to a Pentium 3, and Windows Millenium Edition was installed on the 10GB hard drive. I absolutely hated that computer.