TweetJust keep track of your strength gains. Write down your workouts and make sure you are continually getting stronger and stronger. If you are getting stronger, then the muscles are probably getting bigger.
As for dumbbells, I like regular dumbbells of every variety. I have used the cheap all cast iron and very expensive high end rubber coated dumbbells in fancy gyms. They are all good in my opinion, so go cheap on dumbebells. Power blocks are good if you are short on space. The only issue with power blocks is you can NOT drop them onto the floor. You have to be kinda dainty with them, but they will work.
My chest has never been a problem and all I can say is I have done a bazzillion dips and benches of every type. Thats what has worked for me, but what works for me might not be the answer for you. Try the stuff mentioned in this post. Good luck.