Absolutely DO NOT buy resources from this page:
It is MUCH cheaper to buy resources from the Black market. After upgrading to market 23 you can find resources in pack of 20mil for 8400 gems and after level 25 you can find 50mil packs for 21k gems. It doesn't take a mathematician to calculate that 60k gems for 50 million from the shop is much more than the 21k gems from the Black market. Just keep refreshing and buying what you need if you have to.
Again do not buy speedups from this page:
I'm not going to break down the math for this one but take my word for it; if you are gonna use gems to speed something up just use gems outright as it is much cheaper. Catch enough rallies and you'll never truly be hurting for speedups that bad.