Hi, I'm an audio novice currently own Bose 701 Series 2 floorstanders as mains and I'm thinking about upgrading them (somewhat influenced by Bose bashers I guess...lol)

Unfortunetely I don't have much room in budget (max $600 so I'm looking more into used sets) yet I want to be sure it sounds better than my Bose. I had already compared my set against Infinity Alpha 50 and Yamaha NS777 and my speakers actually sounded better with wider imaging and bass so I had to return them. My current cadidates are:

Pinnacle Gold Towers
or
Infinity Beta 50
or
Paradigm Studio 20 - I don't mind bookshelves as long as they can fill my 23*12 living room.
or any other in that price range you want to recommend

Any help is highly appreciated!!