Mozaic is currently 512Kbps, but Qtel are in the process of doubling speeds wherever possible so this will soon be 1Mbps for the same price.

What this also means, of course, is that if you get the 2Mbps product it will soon be upgraded to 4Mbps (wherever possible) for the same price.

I say "wherever possible" as the speed you can receive is dependent on your distance from the telephone exchange which the ADSL service is delivered from. To get 4Mbps you'd need to be perhaps 2km or less from the exchange. Unfortunately there's no way of knowing in advance which exchange you get your service from.