Not bad
You're right, the samples really weren't the best, but the track itself is really good.
Intro is pretty good, really like the rhythmics you added in the intro, but it doesn't feel like it's building up to much. The bass drum through the track sounds really good, with those somewhat buzzy synths.
The more ambient synths really add to the track as well. Personally i feel a song always can do with some ambient synths.
It all feels a bit random, and some transitions sound a bit out of place. There's not constant flow to the track, it just really moves along, and changes quite a lot along the way.
Ending doesn't sound the best either, it's a bit shallow with just the synth and rhythmics, even though the rhythmics are pretty badass.
Review Request club
I really like the idea of the challenge, though. You did a great job with such limited tools. That alone gives you a bonus point from me, at least.