NES/Famicom all the way.
Btw i don't have a problem with the sms i gave it a chance years ago.
I'd pick it up from ebay and gave it a try for fun since i didn't own one then.
While it's graphics and sound did impress me. It's lack of games that i enjoy on the nes wasn't, there and... it's loose controlls annoey the hell out of me.
So befor long i sold the whole thing i just perfer the nes more.
As for Atari 7800 never got into it so dunno.
I think the problem was just your lack of knowledge of SMS games. Not only is there a ton of great games that were released in North America, there're hundreds(?) more that were released internationally that can be played without any converters/mods. It's pretty much exactly the same deal as the TurboGrafx-16.
As for the loose controls, I know that every game doesn't have crap gameplay, so I'm assuming the problem was your pad. The standard SMS pads with the joystick knob work great, but you can also use any Genesis pad as well. I usually use the Genesis 6-button controller.
Oh i know what's on the system games like zillon,phantasy star,psycho fox and alex the kidd etc.
Still afther owning the system i found out it just wasn't for me.
When i had it i spent more time on my neo-geo,famicom and pce far as retro gaming go's.
SMS was sitting there and collecting dust... so if i wasn't playing it i didn't see the point of keeping the console.
During it's heyday when the i had a nes frist i wanted a sms as well.
By the time i got the system i found out it wasn't for me.
It's all about what your taste in gaming is and the, NES filled my need in what i wanted in a 8-bit system.
Maybe when i get a Wii and if sega offers SMS games as VC title's i'll give it go.
Still that's far as i'm willing to go.