I got a Sony jobby with USB and 3.5mm interface for about that much last summer from Halfords if that helps. FWIW I've had 2 Kenwood units that had an incredibly complicated 'one button / joystick' control (one came with the car, the other was tried and then went back). The Sony has more buttons and is easier to navigate round, although its integrated with steering wheel so not that much of an issue.
Maybe more buttons than you like, but less 'menu's / options' per buttons make it easier. Not the flashiest LCD display, but I like it.
NB – Turn off the 'Demo' option
http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_732205_langId_-1_categoryId_165474
Not fully iPod compatible, you can't cntrol the ipd from it, but reads it as a CD_ROM. But you can plug a USB stick into it rather than carry around all those CDs.