Spacesaver or moneywaster?

So in light of the upcoming move, I thought I would be practical and buy some space saver bags to pack more into less. Now, I am not a professional spacesaver bags user... but I thought I would be able to manage alright. Worst case scenario I'd have to read some instructions. I say all of that with sarcasm of course, you put some stuff in a bag, zip it shut, attach your vaccuum hose to the little spot, suck the air out and put the lid back on. Well apparently I am an idiot I guess. I got out the jumbo bag, pakced it full, sucked the air out, put the lid on, all good. So I figured I would pack up some more. I did two more bags, smaller in size, and all was good. Now as I sit here and look over at them, I am not so impressed. The first bag I did still looks as freezer packed as anything, but the other 2.... not looking so good. I was going to throw in some pictures of the bags in question for evidence but it looks like my 2 hour walk/photo marathon along Roosevelt Island this afternoon, zapped the remaining juice out of my camera! Trust me though, two of the bags have more air in them than my lungs do right now!!How is that saving me any room? All it does in save room in my wallet from where the bills went to pay for the spacesaver bags! This lady apparently is pretty pleased with her spacesaver bag experience... let's just say my bags don't look like that! Anyone have any tips on how to keep the air out of the bag? Maybe I was only talented enough to get it right the first time.