I'm not a cook by any definition of the word, unless zapping frozen dinners in a microwave counts. I had a need to start cooking real food, and eating real meals, so after seeing a friend use a pressure cooker to easily cook acorn squash, I broke down and bought this pressure cooker. Did I say I'm not a cook? I was initially intimidated at the idea of using a pressure cooker. Did I mention I'm not very mechanical either? I was afraid it would be too complicated for me - and I'm not overstating my inability to follow instructions past Step 3. I followed all of the instructions carefully. They are clear and easily understood. Even I wasn't able to screw this up. Voila, I had fully cooked tender chicken breasts in less than 20 minutes, and that includes all the prep work I did using the chicken recipe I found online. Easy cleanup afterwards. I can't give an opinion on aluminum vs. stainless steel. I'm amateur enough to have no opinion about the superiority of stainless steel. It works just fine for me.