Most if not all clear bras will yellow over time - some faster than others - its very related to how much exposure the material gets to elements (sun, rain, dirt, snow, etc) and how well the film is maintained (waxed regularly, etc).
So, for your question, it depends on the useage for the car.
3M is better for a car that spends time outdoors (eg parked at work regularly, parked outside, etc). It has a clear coat on it and is a more durable product. Downside is that it's not as clear as Venture and shows some orange peel in the film itself.
Ventureshield is better (assuming its still the "old" venture product) for cars that are parked inside most of the time (like most NSX garage queens - like mine). It's the most clear product on the market, but is not as durable and scuffs easier than 3M.
So you have to decide if you want clearer or more durable.