I think it depends. The 43" model is about as good as you can do at that size. You're not going to find premium sets at that size range, period. I'd say if you need a TV in the ~40" range, it's a great option.
The 49" is not as good of a deal, IMO- mainly because of the move from the 43"'s VA panel to an IPS one. Once you get into that size range, you're within a few hundred bucks of being able to take a pretty noticeable step up in picture quality by going to a set that has local dimming, higher peak brightness, and a VA panel as opposed to IPS. Just my two pennies.
Even then it depends.
Where I live the 49 was cheaper than the 43. And IPS is better for me, as we don't sit exactly at a 90-degree angle to the TV, and rarely in too dark an environment, so viewing angles are more important than black levels.