If your main reason for getting another PJ is 3D, I think Bulb based would be the best solution. There are some nice models around 900-1300 dollars in 1080p, and 700 dollars for 720p 3D. Look at the first couple of pages of threads on this under 3,000 dollar room for what people are buying and recommending. Or start a new thread on Best 3d and give your top dollar you are willing to spend.
Now, if you are wanting to stay with 3D in 720p in LED, I would think the pa70g would be the hands down favorite. It's the brightest 700 lumens compared to 500 lumens, has 2 year warranty, 6 watts of stereo sound. No start up warm up issues, and if you get a focused model is excellent for 2D and ok for 3D.
I have tried 3d on it, and it works , but it tired my eyes out so much, I'm not gonna go 3D anymore. Maybe others can share their experience with 3d on both LED models and also their experience with bulb based 3d , in helping comparing 3D between Bulb and LED.