Would choosing one of these options really improve the quality of my streaming video?

I just found out Netflix has these options available on their site. They said they are aware of their customers having data plans from their Internet providers so in order to help in controlling usage, the following choices are given.

Good quality. ( up to 0.3 GB per hour )
Better quality. ( up to 0.76 GB per hour )
Best quality. ( up to 1 GB per hour or 2.3 GB per hour for HD )

Now, the quality of my video streaming would start out quite unimpressive. Not very clear at first but most of the time, it eventually gives out better video quality as the streaming progresses.

I haven’t made a choice yet, so I guess my streaming is running on default setting. I’m also with CLEAR for my Internet service, paying 45 bucks a month for supposedly unlimited use.

I’m wondering if someone here in Fluther had to deal with the same choices and could help me out with some insights and recommendation. Thanks.