A lot of guys say they like to have two 210 cabs so they can stack them verticaly , on their sides , so the speakers are closer to your ears when playing . Lots of stages don't give you enough room to get very far out from your amp so with a 410 the mids blow right by your knees and all you can hear is the thump and lows . Also the sound spreads farther to the sides when the speakers are in a line on top of each other , just like at big concerts with all those little cabinets suspended in a verticle line . That's why the speakers for concerts are called line arrays , it really makes a difference .
A 112 and a 210 stacked may sound pretty good , I used to use an Avatar 112 with an Eden 210XLT , and I thought it sounded great . I don't know how the Avatar 112 and 210 would sound together though but all the speaker gurus around Talkbass say the matching speakers of the same kind work much better . They have a much more even sound that way .
When I had my Avatar 410 neo I had a hard time hearing it on some stages and I think it was just what I said before , the sound was blowing by my knees and I just couldn't hear the mids . I think if I had the 2-210 stack I might have kept it . The Avatars do sound very good if you get the 410 or any other cabinet though .