Ok, so just did a bit of math and the Gossamer Gear 1/4" Thinlight pad is a lighter material coming in at 5.11-7.5 oz/sqyd based on their weight variance. The Big Lots EVA Antifatigue floor mats comes in at 14.55 oz/sqyd. So the GG Thinlight pad is lighter weight.
For comparison, the Walmart blue CCF pad comes in at 0.09oz/sqyd.
The one advantage I see thus far with the Big Lots pad, besides price, is that you can cut it to include shoulder and thigh wings which the SPE is designed to add. As far as price goes, you can get two 23x96 full length pads or three 33x48 torso pads out of it for less than $20. Not a bad deal if you ask me. I've not tried laying on it in the hammock outside yet, although if I get the urge I may setup outside tonight and enjoy the frosty 30s.