Up until now I have relied on my Silver 5i floorstanders to provide the bass in my system which is driven by the Arcam AVR300 but have decided it's time to add a sub to get better bass extension. I ONLY want the sub for movies - I'm not a bass junky and am quite happy with my existing sound for music. While I want something to add a bit of depth to explosions and special effects etc, I want something that adds depth not boom so the bass must be tight and fast. Since I intend this to be a fairly "subtle" upgrade and don't want a "monster" sub, I don't want to go mad so was thinking of maybe MJ Acoustics Ref 100 or REL Quake at around £350 each. Any comments from those with experience of these subs or any better suggestions would be much appreciated. Thanks.