Before you do switch to another network operator, it can be worth it to ring them up, and complain.

As with any service, the more complaints they hear from people the more mo bile operators will go to lengths to improve a service.

If its something like network coverage they can fix these issues quite easily. Something like speeds, can be alot trickier.

Still it is worth ringing them and lodging a complaint.

BUT, understand: it is practically impossible to get the full network speeds they offer "3.6Mbps/7.2Mbps".

Hope that helps.