I loved both versions of this movie. Honestly, Vol. 1 may be one of the best action movies I've seen in a long time. Almost everything about this movie is perfect. If you're not a fan of the grindhouse cinema that this movie is a tribute to, I can understand not liking it, but I thought both parts were amazing.
And as for splitting the movie in two, that wasn't Quentin's first choice. While making the movie he basically kept coming up with more scenes, then filming them. In the end, he was left with what he though was a solid 4 hour movie. The Weinsteins at Mirimax said there was no way the movie watching public would pay to see a 4 hour movie of this type, and refused to release it without Quentin cutting it down to 2 or so hours. Quentin refused, and they eventually settled on splitting the movie into two parts. hence the two parts.
I'm looking forward to seeing the whole version in theatres as it makes its small realease, art-house tour.