I tend to find they are average/good on a rotating cycle
AC1: Average
AC2: Good
AC3: Average
AC4: Good
Unity: Average
Syndicate: Good?
I've played them all to the point that I realised that I was just playing them out of habit, and time filler, as they aren't any fun.
AC2 and Brotherhood best, and Black Flag a good change, but generally the series is stagnant and needs putting on hold for a few years. But not going to happen as long as Ubi can milk it.
That aside the way Ubi treats gamers, bugs, performance issues etc means I'll no longer buy their games until they're extremely cheap and have been patched several times.
(AC3 is mind numbingly boring and takes an age to get started, by far the worst)
Considering the mess that Unity was on launch I really wouldn't upgrade for this game.
You can get it for 20 on key sites, i managed to pick it up on ebay for 17 and am looking forward to the london setting
I don't understand people who buy things before they are even released...do you enjoy being bent over by publishers?
Especially after the fiasco that was the last game, that took 5 updates before it was 'playable' and I use that term loosely. It was so bad I had to have 2 installs on my PC, one patched and one unpatched just so I could switch between them depending on the bugs.