I installed the MP oval track springs on the Scamp last weekend and had the same thought. As soon as I set the car down, the springs did the typical reverse arch, so I took the bottom leaf off and spun it around so that the longer end of the spring was supporting the forward section of the pack.
That took most of the reverse arch out of the forward section of the pack.
My take was screw it, they're junk anyway, have nothing to lose.
I've put about 500 miles on it since then without any problems.