I personally have decided to not use the Wodent Wheels, although I did originally. I had a senior for my two girls. They definitely did enjoy hiding inside of the wheel, however I was always worried that one would stick their head in the wheel while another was running, and then get their neck broken. That never happened, and I haven't heard about it happening to anyone, but it did make me worry a bit.
I also found that the wheel got very stinky very quickly, and it was very hard for me to clean. I think the combination of the solid running track (mesh allows more poop and pee to fall out of the wheel) as well as the closed face of the wheel caused urine and feces to get stuck in the wheel. Then your gliders are running in their own mess. It can make their bellies yellow, and it stinks up a cage very quickly. Yeah, you can clean the wheel, but the way the parts fit together involves this very tricky clasp. I always had a SUPER hard time taking it apart and putting it back together. It drove me nuts.
Now what really made me stop using the wheel was a thread on here. Someone posted about how their glider's tail got caught on the horizontal bar inside the wheel. Their tail broke, and they had to get part of it cut off. The day I read that thread, I took the Wodent Wheel out of our cage and ordered an Eco Raptor. However, as bjve31 mentioned, you can purchase an axel guard to prevent such an incident. I WOULD NOT USE A WODENT WHEEL WITHOUT AN AXEL GUARD.
Other good wheel options are Raptor wheels, Stealth wheels, and Fast Track wheels. I only have experience with the Raptor wheels (they're made by a Texas vendor, and I'm a Texan). I believe all of these wheels lack the center axel and have mesh running tracks. Gliders seem to be able to run more naturally without the axel in the middle of the wheel and with mesh they can grab with their little hands. (They jump more than run, really). I realize that the Wodent is one of the cheaper wheel options, so might I suggest the Eco Raptor, which is what we have? I want to say the wheel is like $26, and shipping brings it up to around $30-35. It's the cheaper Raptor option, and I believe the next cheapest option after the Wodent. It is all one piece, so you don't have to take it apart to clean. Like the Wodent, you can get nail trimmer inserts for it. Gliders can also hang on the mesh on the OUTSIDE of the wheel and have a blast (super cute to watch) while the other runs on the inside.
Whatever wheel you get, you should follow two important rules. 1) Clean the wheel (and all glider toys, really) before letting your gliders use it. You can never be too safe with these little guys. 2) If you opt to get a wheel that sits on the floor of the cage, rather than one that attaches to the side of the cage, made sure to secure it. I use a strip of fleece to tie my wheel to the cage bars, otherwise it can easily move around the cage while the girls use it, and I don't want to have any accidents.
Good luck!