You look awesome with your bike!
I bought a bike that I've ridden a few times too. However, considering most of the time I was losing was during bad weather months, I wouldn't have been able to use it all that much. However I DID take spinning classes religiously...actually I've been a faithful spinner for over six years!
I know spinning incorporates both strength and cardio—just like a real bike. I love how my legs turned out as a result. While there is some loose skin at the very tops of my thighs, it's pretty minimal and it seems to be shrinking.
My thighs actually still rub together, but it's not because of the fat
They're muscular! Poke one and your finger wouldn't sink in much at all—it immediately hits muscle.
I have no scientific evidence, but I know if us formerly obese folks strength train that we keep most of our muscle when we lose weight. We also have muscular legs from carrying around the fat. I'm wondering if between the spinning classes and weight training that I do that my legs just kept the majority of the muscle I had to begin with.