I own a few different brands, but most are polk and I've been a long time owner/fan.
Ever since I've owned my rt7's I've loved the polk sound, especially on vocals and acoustical instruments.. non-fatiguing.. That midrange.. mmm. mmm... The rti38's are close, but I still think the old rt7's may sound the best still. Havn't really had the cash for the lsi's but if I find a good deal on used pair ill probably buy em'.. Their ip active speakers are very interesting, cool to see them at the forefront. I think that is going to be the next big change is having active powered speakers that hook up with ip or other digital protocals.