Older vs. newer REL subs


Looking for any reports about older vs. newer REL subs.

I have a REL 328 (ca. 2013) which I bought used. It's a good sub.

https://www.hifiplus.com/articles/rel-r-328-subwoofer/

I would like to upgrade to stereo subs and I've found (finally) another REL 328 which would match mine. But, before I drop coin on that, I'm wondering if anyone has had experience comparing their older REL with a newer one. What's changed? What's better, worse, or the same? I'm considering the T7x and T9x lines.

Hoping for apples to apples comparisons, vis a vis driver size, type of sub (e.g. level of product line, sealed vs. ported, music vs. HT etc.) but whatever old vs. newer comparison you have much appreciated. 

Thanks.
hilde45
@wolf_garcia wolf_garcia
"...The bad news is that REL won’t service them. If one dies I would try to find somebody to fix it,..."


Good point to bring up for others to see.  This is the problem with buying older -2 prior generation used subs, and when the factory no longer stocks the replacement boards, amps, parts, drivers any more. It becomes a best effort self-fix situation.   Helped many friends rip out stock amps and drivers to replace with generic Dayton 250/500 amps and other drivers to keep them going. Got two DA 500s sitting her right now in fact.    So what's left, a cabinet? Rather build a new Rythmik or Dayton kit sub with a good driver than buy a 5+ year old factory sub that you can't get parts for any more because they've moved on to different designs. Just something else to be aware of when buying used vs. new subs.  And they DO rattle themselves apart after 5 years, and less so when when used more sparingly.  They want you to buy the new model when it happens, fwiw.   
"I'm not in the market to buy two $2500 subs to replace a single older $2k sub; I would entertain two newer $1500 subs, however" .......you can buy the S510 for 2 grand brand new delivered...if you would buy (2)1500.00 subs and not entertain (2)2000 subs which are much much better your wasting everyone's time here with this post as thats just stooopid
@missioncoonery Where is the S510 available for $2k each?

As I price it out, I paid $1k for my present sub, used. I can probably get $600 or so for trade in with the folks nearby who trade and sell gear; if I get two $1500 T/9 subs with them, it totals $2300 rather than $5k. That saves $2700. Not chump change for people who work. If they’re all good subs and my system is not a $30k+ system, that sounds like a fit. More seems like overkill, though I know that’s the name of the game in this hobby for many.

But let’s take your $2k price as something really available (I assume that you’ve got a link for me on that). Let’s also assume that there is no trade in involved. So, essentially what you’re asserting is that someone who would prefer not to spend $1k or a third more is "stoopid" and that this discussion is "wasting everyone’s time here"?

I laid out my parameters and preferences in the OP and my posts, so I’ll leave it to others to decide if I’m wasting their time. Doesn’t seem like it, based on the helpful posts. Of course if you feel your time is being wasted, you’ve got options.

Again, my REL subs have been in fairly constant use and haven't rattled apart at all...I've taken them apart and would notice anything rattling. 
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