I have the 42PZ85 and it's an excellent tv. Excellent motion handiling (as long as you turn off the IFC feature in the menu), really natural colours, excellent black level detail, even the sound is good by flatscreen standards especially if you use the BBE VIVA 3D fake surround setting. Nice remote and even the tv stand swivels on it's base which is handy for plugging in all your cables.
SD from a bog standard SKY box is pretty impressive for a full hd tv, upscaled dvd's through a PS3 look amazing and blu-ray's take your breath away. I was completely blown away the 1st time I watched a blu-ray, really detailed and the picture looks 3d.
It's an excellent tv if you like games, really fast response time so games like Burnout or GT5 in 1080P look really impressive.
It does take a bit of tweaking to look it's best, but 10 mins with the THX optimizer works wonders.
I havn't seen the Sony to compare to mine, but I love my tv.