I really wouldn't advise kicking or punching those tbh. Might get hurt in the long run, they pose a bit too much resistance.
We strike tyres with sticks in Eskrima to train our power and accuracy against a solid target. And even with a freaking stick you can feel the tyre fighting back a lot. I do sidekick them at times just for the fun of it, but really, I wouldn't advise training with them.
The sandbag idea is in my opinion the cheapest way to go. My Sifu normally recommends iron sand, which I'm still unsure as to where to find it. He says he used to train with iron sand bags back in China...
tyres could possibly be good for teeps i've never tried though, i have seen tyre punch bag system a few times and wondered if it was of benefit, and think it may be just a cheap way to do things in thailand, i would hit a softer bag and thai pads for a while to condition shins before hitting harder bags, if you try and dead shins to quick you will damage shins.