One nice thing about the Shuttle 9 is that is sounds really nice with many different cabs depending on your tone goals.. My tone goals vary from gig to gig, since I'm a bass mercenary..
I have used and own Aguilar Db and GS112s which does rock real well.
The GB Neox112 work great in many situations.. they cover a wide band of styles for my tastes. Has alot of grunt and clarity with a decent controlled bottom.. and it s the lightest of the bunch that i have played.
I have a bergantino HT112EX which i use for smaller gigs and singer songwriter stuff sound incredible and is the smallest of the cabs for easy moving where i dont need to rule the world.. But i bet a pair would be real nice.Very smooth from top to bottom.
And i used a friends Schroeder 1210 R which suprized the heck out of me how loud that and a Shuttle 9 will go on a tom petty type vibe band with guitars playing AC30s and a Hammond B3 with big Leslie.
The Schroeder's although not being big in the botom end somehow i forgot about that when i was able to really hear what i was doing easily since they are so mid punchy.. And i say that in a good way... The Schroeder was the loudest small cab that i personally have ever played.. and it cut through with ease..
Have used it on 810s and 412s too. and it drives the heck out of all of them...
I guess what im trying to convey here is that i have found the Shuttle 9 to sound good with a wide variety of cabs. So just about anything you get will sound good...
The HT210 form what i understand is sort of scooped... IIRC....
If you are set on a Berg setup.. and a few extra pounds wont bother you. the HT112ER is the way to go.. The AE112 is cool too, but personally i like the HT. just sounds a slight bit smoother in the upper mids to me..