I've recently upgraded with an Autodelta induction kit which looks really good and is simple to fit (

take care removing the air flow meter plug-in though, it's a fiddly little bugger and you don't want to snap it), it also frees up much needed space under the hood and puts more engine on show. There's not too much difference in sound though you can hear a slightly lower burble and the performance increase while not huge it is definitely there. It feels sharper on the move and just feels like less effort to accellerate through the gears.
So for a simple, cheap upgrade that actually works it's certainly worth doing.