Hi

please help i'm looking for a bag for commuting to work, is it worth buying a bike specific one eg http://www.deutergb.co.uk/products/all/Bike/All_Bike/

Ta 

Get paniers or a top bag on a rear carrier ( or both depeding how much you want to carry).

 http://www.deutergb.co.uk/products/all/Bike/All_Bike/Rack_Top_Pack/28/

 Check out Wiggle for bargains.

Thanks for that is the top bag better than paniers?  I have never tried paniers?

http://www.deutergb.co.uk/products/all/bike/all_bike/Rack_Pack_/30/

I've been using the Hydro12 for my short trip to work and back (bike won't fit paniers). 

http://www.deutergb.co.uk/products/all/Trekking_+_Travel/All_Trekking_+_Travel/ACT_Lite_45+10_SL/84/

I can fit a my change of clothes and towl in there plus it comes with a 3 litre bladder and tool/pump holder etc.

thanks actually have a bladder from them already and love it

http://www.deutergb.co.uk/products/all/bike/accessories/Streamer_2.0/46/