I had exactly the same experience on Vfe 4G. Faster speeds over a tunnel, either VPN or Andrews and Arnolds un-encrypted L2TP. In particular I found traffic from Usenet ports was particularly aggressively throttled. To be honest, it is a mute point for me now because just before Christmas something changed at my local mast and the signal strength down considerably and bandwidth took a massive nose dive to the point it was next to useless. Bandwidth has improved to the point I can just about manage with it for now. Vodafone refused to admit that anything had changed but I pretty sure the problem is their end - they were extremely unhelpful. Earlier in the year I was getting ~45Mbps but dropped to dropped suddenly to under 3Mbps Now it is about 14Mbps. Truespeed are busy installing in my village so hopefully that will be up and running in a few months. To be honest, I feel my fingers have been burnt with mobile broadband and I am keen to ditch as soon as I can.