I like liquid. I feel like I have more control. I'm learning more and more how to understand therer needs so I can give her a little of this and a little of that.
Now my tomato's and shrubs get those slow release spikes. They work great.
Results wise. I get a huge difference when I feed my girls liquid. Like am overnight difference.
I think liquid is much better than slow release in the results department.
But if ypour guerilla growing, or don't have time, use the spikes.
(This is just my opinion, based on my experience.)