We need to know how big the boxes are.

One thing you might try, is to upgrade your amp first and see if that stops the speakers from 'complaining'.
An overdriven amp makes a square wave that sounds an awful lot like a blown speaker.

Another important option. One that is better than putting new speakers in, is to just recone your existing speakers. Send them to orange county speakers. Get them reconed.
It is better than trying to fit a new pair of speakers into a questionable box. By questionable I mean. Boxes are sized specifically for certain speakers and it does not always pay to just upgrade to a more expensive speaker.

The best option is to recone your existing spk's and buy another set of sub's. If your old speakers did a good job than you should buy another set of those exact same speakers.
You cannot fight physics with money.
Sometimes more is better.
If you want to keep from wearing out drivers I would suggest getting the amps out of Mono (I run mine in mono mostly) and driving 4 boxes in stereo (2 per)

There are two good reasons for this.
Sub frequencies rely on quick transient attack. Most dance music has a steady deep bass. And then it hits some really low notes. Which draws AC power and txes an overdriven amp. Basically, everytime you see the amp lights go into red, you can be sure that toxic square waves are being unleashed into the sonic atmosphere. This is pollution of the speaker/amp killing kind. And it also causes aural cancer, the kind that can kill a reputation or just harsh a good party.

So if you need more bass, the best solution is either better AC, and or more speakers and amps.

It doesnt work in the dance music universe , to just crank up the amps. It hurts.