I used it quite a bit last year and used it this year for the first time last night. I live in Texas so it is just now getting "cold". I have actually been surprised at how good a distraction it is. Someone on Slowtwitch asked about it and this is what I wrote there:

I have ridden/raced over 200 "kilometers" on it mostly on last year's development version and will be using it this winter as well. I found that whether racing against algorithms or real people it provides motivation that just riding on a trainer or rollers doesn't. It is interesting psychologically that having a graphical representation of a real person trying to beat you to an imaginary digital finish line really will make you work harder than you would otherwise.

Basically you will have two types of races. Those against all Artificial Intelligence riders and those against AI's mixed with humans. Personally I think both are fun but the humans are less predictable and so more interesting. For the AI races they will have differing abilities, and I believe they are chosen based upon your race history. So if your race history shows your average watts to be 200 you aren't going to be stacked up against a bunch of 400 watt AIs, but for your first few AI only races you may win them easily while you develop a history. The drafting and calculated "speeds" (I'm using air quotes there since you aren't actually moving in real life) seems realistic from the visual cues on the screen. When a real person joins in the race it provides even more motivation. The 3D is constantly improving but for me that is secondary; just having the visual cues of other riders, different terrains and elevations, and speeds calculated based upon real physics, whether it all looks cool or not, is the best part of the program. The added benefit is it just keeps getting better visually and has gone all the way from a red floating cube to pedaling people with trees, windmills, towns, etc.

I think it is great and worth a try even without the try-it-before-you-buy-it offer. I have even hooked it up on one computer with TrainerRoad on the other and just rode a time trial on TdG while I was doing TrainerRoad intervals with the little 3D me on the screen speeding up, slowing down, speeding up, slowing down, etc.