I recently installed the InstaTrunk on my 4 door. I removed my factory sub and installed an 8" powered Bazooka tube. Here's my 2 cents...

The InstaTrunk works great for me because it gives me a secure place to keep the sub from growing legs and walking away when I'm out & about with the top down. It's also designed so you can still easily access the storage area in the floor.

Also, I like the fact that it doesn't occupy the entire area behind the back seat. 9 times out of 10 I'm putting stuff back there that won't fit in an aftermarket trunk anyways. You can still fold down your back seats and have plenty of open storage space with the InstaTrunk.

I don't know much about the FlexiTrunk, so I can't compare the two. I guess it all boils down to why you need one over the other.

EDIT: I should have added that this trunk utilizes factory mounting points. You don't have to drill any holes in the tub.

Here are a couple pics...

 

I have been thinking of picking one of these up for the same reason. My sub and amp are way too noticeable without the top on. My only real question is does the insta/flex trunk rattle from your sub?

 

No rattling at all. The trunk is one piece. It installs over your carpet, eliminating metal to metal contact which could cause vibrations.

 

WHat seems to be more secure between the two? I believe the instatrunk is all metal compared to the flex being plastic so I'm assuming the instatrunk would be way more secure. Is this true?

Also, I still don't understand what you are talking about when you say it doesn't cover the whole trunk area. Your first photo doesn't have the seats in the photo so I'm having a hard time visualizing it. Does anyone have a photo that shows the seats and how much waisted space there is?

Thanks!

 

Anybody got any good pictures of the FlexaTrunk other than whats off quadratec? Once my hardtop comes off i think it would be key.