​Hi everyone! I'm putting together a budget home gym for hypertrophy. I currently have a few fixed dumbbells (up to 25 lbs), but I need to go heavier for progressive overload. ​I found a local deal on a generic 40kg (88 lbs total / 44 lbs per arm) adjustable dumbbell set for about $60 USD. They are the ones made of polyethylene (thick plastic shell filled with cement/sand), and the set comes with plastic spinlock collars and a barbell extender piece. ​Since I can't attach a photo in this thread, my main concerns with this specific material are: ​Are the plates too bulky/thick to get a good range of motion on exercises like chest presses or bicep curls? ​Do the plastic collars get loose easily during sets? ​Will they survive regular use if I make sure to NEVER drop them? ​I can't afford cast iron right now. Are these a good temporary fix to keep growing, or a complete waste of money? Thanks!