15 mb quart rwe 354 vs 15 jbl gto2d

Okay, I plan on buying either two of the MB Quart, or JBL subs that I listed in the subject line. I'm pretty confused with something though.
As far as the specs go, the MB Quart seem to edge out the JBL just slightly in the frequency range.
16-300hz for MB Quart, and 23-400hz for JBL.
Also 700rms/1400peak MB Quart vs. 300rms/1200peak JBL.
So looking at those numbers right there would tell me I would get a boomier deeper bass from the MB Quart. BUT, I talked to a local shop that sells them, and they said I would be disappointed in the bass output from the MB Quart if I liked to listen to rap, hip-hop. They said they are meant for SQ.
I dont get how that can be from the specs, the specs would seem to state they would be better.
I used to have two of those 15" JBL subs and I loved them! Were very loud and boomy. So thats a big reason I want to go with them again, because I remember how they sounded. But The MB Quart specs look better to me, I guess the differance would be in the motor design, or some other stuff that I dont know about. Here are some quicks spec links, thanks.

https://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=3417&Cfid=4950483&CFTOKEN=ddede3cc6fa51961-50C18634-1422-7C6E-50F780E50A79A7D1

https://www.sonicelectrnix.com/item_7441_JBL+GTO1502D.html#specs

Oh yeah, these subs are what are in my price range so that ended up being the deciding factor, even though I have been recommended better subs, but I can only buy what I can afford.

Can anybody explain to me why the JBL might produce a better bass then the MB Quart, or are the MB Quart's really a better sub woofer ??

Both will make bass...how loud that is and how good it sounds depends on the ENCLOSURE