I too have a gaggia classic and after many trials and tribulations have almost got to the point where I'm getting constantly good microfoam (the art, however, is another matter entirely).
I took off the foam enhancer 'thingey' and now just use the small plastic tip (I 'float' the first circle of this plastic bit on top of the milk at an angle - so just the few mm tip is immersed).
I'm pretty much always making two cappa's/small lattes so found the 12oz jug a little too small (had to make two and was always left with a little waste).
I've now got the 20oz jug:http://www.happydonkey.co.uk/hd08...k-foaming-jug.html
and the foaming has improved by a long 'stretch' (sorry). I think, as somebody else mentioned on this forum, that it's due to the larger portion of milk have longer to heat up. This jug is being used with the aforementioned tip above. I've not had any 'soap' bubbles from it at all, just a nice glossy cream.
I may however add a Rancilio Silvia wand over the next month or so.