If you play almost exclusively 72 pin North American or European NES games, buy yourself an AV Composite modded NES-101. Done professionally buy someone who knows what they're doing, the AV signal will be just as strong (or stronger, depending on the skill of the modder!) as the NES toaster, plus it'll be a HELL of a lot more reliable than the origianl design.
If you play 60 pin Japanese Famicom games a lot and maybe some 72 pin NES games here and there, get an AV Famicom, the Japanese model of the NES-101. The AV Famicom is composite already, and in fact uses the same multi-video out cable as the SNES, N64 and GameCube!
Both systems will cost around $80 minimum, but think of it as investing in systems that won't ever give you issues.
The guy I got to mod my NES-101 [toploader] is akaviolence who runs a pretty interesting site as well as an ebay store selling NES and tech stuff. He charges $40 to add standard RCA composite video jacks with CLEAN jailbar free video to an NES-101, $5 to add a power LED so you can easily tell when it's on, $20 for pseudo stereo [wherein the left channels get the two pulsewaves and the right channel gets the triangle and noise channels, creating a dynamic soundscape that can dramatically improve the listening experience of many classic NES and Famicom games] and $20 for overclock switch that can be toggled to remove any slowdown that occurs when some games exceed what the NES can handle at once.
So why would I, a seasoned modder myself, get someone else to mod my NES-101?
According to him, his site and his ebay track record, he's been AV modding NES-101s for years and has probably the most experience doing it anywhere.
Here are the links. You'd need to contact him and figure out what you want and go from there.
his site: [lots of images, including images of NES-101 decked out that I bought from him]
http://www.game-tech.us/pmwiki/pmwiki.php/Nes/NES-101Modshis ebay FAQ:
http://reviews.ebay.ca/Nintendo-Top-Loader-NES-101-NES2?ugid=10000000015725070AV Famicoms can be found in many import shops online, or ebay.