Upgrading my speakers

Question

I currently have a pair of Kenwood Floorstanding main speakers that are about a year old (got them at a clearance sale for $200) and a Kenwood rear and surround package that cost me about $175. I was thinking about upgrading my speakers, but I want to get bookshelf speakers this time around. Here's what I was considering:Polk R10 or R25i for mains and surrounds Polk CS245i for centerAre these speakers any good or should I consider Paradigm or JBL?My other question is: Will the bookshelf speakers have poor sound compared to my floorstanding ones? The room size is 24' L x 11' W x 8' H and I have a 100W powered sub. Also my reciever is a Pioneer V509s (5x100) and they will be used for 80% movies 20% music.Any advice would be appreciated