I think it depends on what shape the hole is and where the hole is. If its on the flat bottom of the tank, That product will probably work fine.  If it's near the valve or outlet and is NOT a flat area, that mesh will be harder to fit into place.

I used  some of those Epoxy Putty sticks that I bought from WalMart for $4.00.  It come in a long cylinder shape,  Green on the outside and White in the center.  About the diameter of a Quarter..  Kneed it together till the color changes to grey and press it into the crack. Let cure for 24 hours and test to see if you solved the problem. 

Oh first clean the area around and the crack or leak itself.  I took a wire brush on a dremel and buff'd it clean and sprayed it with rubbing alcohol to degrease the surface. Then apply the epoxy-putty

Here is another repair kit

http://www.rvdiscountsuppliers.com/rv-parts-repair-sealants.htm