I have a 2007 Ford Focus and a SanDisk MP3 player. The way I see it, I have two options: an FM modulator and an auxiliary input converter (http://www.logjamelectronics.com/piefrd04aux.html). The input converter will probably cost about $100 after shipping, but it's something that I'll use for a long time, at least until I get a different car. However, the FM modulators seem to be much cheaper, but I question the quality of the sound. Anybody have any advice? What are the pros/cons of the FM modulators? Do you think it's worth the extra money to go for the auxiliary input converter and have my MP3 player wired directly into my car's audio?

get the auxilary input converter you will be much happier overall.

dude get a FM.....i have a monster cable...and iv had it for a bout 6 months and it works great

Check with a sound shop. Best advice you get.

I'll tell you the truth... the FM transmittters aren't all they are cracked up to be...the reception isn't all that great and if you get a battery powered one, thats more you have to spend each time a set of batteries runs down...personally i would invest in an aux input jack...

If you're planning on keeping the car for a while, definitely get the auxiliary jack. I spent $160 on mine, which is specifically for the iPod and allows me to control my iPod through my stereo controls and charge it at the same time, and I have yet to regret a penny of that money. For something that you use as often as an MP3 player (I use my iPod in my car every time I drive anywhere) you can consider it an investment.Speaking from experience, as a person who really values audio quality and likes to play their music loud and clear, FM modulators are OK if you don't want to turn up your music. Even the best FM modulator I've ever tried, and I've tried several, still produced a small amount of static hiss. And this tiny hiss isn't tiny at all once you try to turn your music up, which I do quite often. If audio quality is important to you, and it sounds like it is, hands down to the auxiliary input converter.Best of luck.

u want the aux input because with the FM thing if u go into a city then the station will take over the one u are using in the car and with the aux, it's always going to work great no matter where u are

aux has much better sound quality, if u hav the money get it.

fm modulator have very poor sound quality i found the aux interface for $75.00 http://www.oemautosound.com/pc-192-86-pie-frd04-aux-ford-auxiliary-input-adaptor-new-radios.aspx