15g plastic fermenter: Open or Closed head?

So I'm about to order a couple of 15g HDPE containers to use as fermenters. I was initially considering closed head but now I'm wondering if the open head would still work well. Reading the discriptions the open head containers say they're not for liquids. I imagine the seal wouldn't be 100%. I'm wondering if any of you are using or have used similar containers and what you think about the seal. Is it good enough for keeping nasties out of my beer? My plan is to add a Better Bottle racking assembly to these. BTW, here are the containers I'm looking at:

Closed head:


Open Head:

The closed head gets a pretty decent seal. I'm using on for a MLT. I don't see why it wouldn't work. It would certainly be easier to clean than a closed head.

Side note: I picked up mine used for $15. It was previously filled with cooking oil. You may be able to someone in your area who sells them.

I have a couple of the open head containers that I use for maple sap collection. The lids seal fairly well but not perfect. They are easier to clean than the closed head.

Yeah, that's the reason I want the open heads, so I can clean it easier. Not to mention installing the racking assembly and a thermocouple!