If the 5.3's sounded good, and you have some room to leave some air behind them in your room, you should go with them! You liked them! It is no harder to get a good sub to integrate w/monitors than w/floorstanders; the RELs, for example, have tons of fine tuning to accomplish this with any kind of speaker. As far as the Vienna Acoustics go, I don't believe they have rear ports, or need a ton of space behind them. The fact is there are a LOT of great speakers out there, but you have the great advantage of having heard the soliloquies. Did the dealer let you listen to them in your home? Or will he let you return them if you get them home and can't get them to sound right?