Homeplugs. What's the best one to get for a UK household?

I live in a house with pretty dense, thick walls that wireless just doesn't penetrate well. I'm looking for a homeplug kit to essentially bridge to halves of the house together, each half broadcasting its own respective wireless network, allowing devices to freely roam between them.

What's the best kit on the market right now in terms of pure speed, low latency and reliable uptime? Usage will be mostly gaming, HD streaming and LAN filesharing between my devices.