I haven’t used those but I feel you. I’m 26 and was always the girl who could eat a buffet on her own and never gain an ounce but when 25 hit, BAM! I gained around 20 lbs in two years. I am NOT happy about it (although its nice to finally have some girly curves as apposed to the skeleton figure I had previously). I want to lose around 10 lbs as well. I mostly am concerned about tightening up my belly and neck. I grew a dewlap!!!! 
I have been trying to ride my bike more but it really is rough on my knees. I have found a couple of exercises that seem to be helping me. Maybe they will help you!
1) I lay with my back on the floor, knees bent and feet flat on the floor. Slowly, I raise my hips and push them up until my back is arched and I am putting most of my weight on my feet and shoulders. Then, slowly I let my body back down. We used to do this when I was in dance, I think it is a pilates move and I know that this was one of the exercises my mom was given when she had back surgery so it is safe to do! I try to imagine that my spine is a pearl necklace and someone is picking me up from my hips, allowing only one pearl at a time to raise. Each vertabra, in this scenario, would be a pearl.
2) I saw this one on one of those late night infomercials where meat heads yell at you for sitting on the couch when you could be dancing your way to fitness. Stand with your legs at shoulder width. Raise your left arm out in front of you and your right leg out behind you, you dont want your leg to go to the side, you want it directly behind you. Reach with arm and leg as if you were stretching your body out. Raising your leg behind you as high as possible. Lower arm and leg. Squat. Raise up. Repeat using your right arm and left leg. When I get finished with this one, I feel my thighs/abs/love handles and butt burn like mad!
3) For the dewlap (turkey neck), I found this on youtube. Dont know if it helps or not yet but I feel better that I am doing something, if nothing else. Turn your head to the left, look up, stick your lower jaw out so you feel your neck tighten, stick out your tongue. Relax. Turn to the right, repeat. Face forward, repeat. I do these in the shower because they look really really weird.
Now, if only I had the self motivation to do these more often, I might see some more progress….