On the uncapped 3mbps connection - a little hit and miss to be frank. When it's good it's awesome, when it's bad, well then it's bad. I would definitely NOT be going uncapped for gaming. Pingtests (Pingtest.net) typically come back with line quality being C or D (packet loss of 2 -5%, ping times of 70ms - 100ms and jitter of 40ms) but often (too often) get a line quality of F (packet loss of 5% to 30%... ping times of 500ms+).
This unpredictability makes it really no good for anything else than mail, web and downloads. VOIP is a no go, Youtube / streaming is painful as it's flying one minute then just hangs even streaming simple 128kbps radio stutters at times (and I'm talking weekends, so this can't be shaping). For normal web is fine (latency is sometime noticeable) and downloads is great, i typically get 330 - 350KB/s on large downloads (granted they typically happen overnight).
So really a mixed bag, can be great for what you need, but can't see anyone gaming on this nor streaming audio / video unless you are OK with a 2 minute video pausing 5 times...