Sound deadening on the cheap...?

[Fastra]

I'm installing some new speakers in my Astra and have read somewhere that rather than spending a fortune on Dynamat cheaper alternatives can be found such as Flashing Tape from Wickes:

100mm x 10m = £10.99
http://www.wickes.co.uk/invt/243009

but I've also found some similar stuff on ebay:

75mm x 15m = £9

http://www.ebay.co.uk/itm/15m-x-75mm-Waterproof-Fl...

... but do you reckon the ebay stuff will stink the car out due to its bitumen adhesive??

Edited by Fastra on Friday 1st July 14:25