Most of the commercial home use kits give OK results but they never last for long..besides..you risk the chance of damaging your teeth enamel if they are used improperly. I recommend you consult your dentist first for a professional teeth bleaching or whitening then if you are not convinced or think you should not pay a dentist for the job then ask him/her if they would recommend any of the branded kits on the market which you could easily find at any Boots pharmacist...
Cheers