I have no experience with a heat plate, But the MHP was great the one time we did it. Here is a picture from the first few days. After just a few days we moved the chicks and MHP to a brooder located in the run.
I did a short article on our experience. Brooder in covered run - Updated 7/11 Six weeks
Good luck
Looks like you've got your pad wrapped securely around it and the frame so no wire is showing? Here are photos of my outdoor brooder, which I had to elevate inside the coop, as one of my hens (sometimes two) plop their eggs on the floor, so I made a little box for them to use - which meant I had to build the brooder on top of that. They have a little pop door to get to some steps and ladder, and I know it's a long drop, but I'm trusting their instincts as to how safe and secure they'll feel before they attempt to reach their outdoor playground (maybe 5' x 2.5'?), which is safe from the hens inside the coop's covered run. So far, at approx. 9-11 days old, they stood at the entrance inside their brooder, with one of them being brave and hopping out to the first step, but going no further. For the heating pad contraption, I put some press n' seal on the bottom of the wire rack to prevent heads getting wedged in there, but I'll have to keep an eye for the chicks pecking at it.