I bought GO Isotonic Energy Gel - 30 Pack (Blackcurrant)
Save 50%
Special Price£22.50 (I bought 2 packs so no postage).
So Lidl is a bit cheaper but there are no Lidl near me (Lots of Aldi!)
If you get on the SIS email list they are always offering special deals.
I once bought bulk boxes of gels that were meant for the US market and were printed with US data but I think were within a year of the sell by date** and presumably could not be shipped there for sale - or something - and so were ridiculously cheap.
** I think there were so many I didn't get through them in the time - but (as you see) I'm still here!!!
Be careful consuming all those gels Graham. They may get you up Trapping Hill but they'll rot your guts.
I'm with Moley, use them for emergencies only. In fact I've just looked in the cupboard and noticed that I'm still on "Best Before" 30/09/2018!