First of all, definitely check out ProjectorCentral's recommended list. They have some great reviews and comparisons. Also, you have to go over to the AVS forums. Everything you could want to know can be found there.
I picked up an X1 last year and, at least at that time, it was pound for pound the best bang for your buck. But, as usual, technology changes rapidly. Instead of giving you actual PJ recommendations, I will give you some advice from someone who spent a lot of time researching/obsessing over this.
First of all, your viewing habits are extremely important when considering this decision. For example:
If you watch primarily DVDs, than a simple 800X600 will do the trick. Present DVD format limitations cannot take advantage of the higher resolutions. I did a side-by-side w/ a Sony HS10 and kept up with it....on movies. The Sony still had a somewhat better picture, but definitely not worth triple the pricetag of the X1.
If you watch HD material, then you need to at least look at the 1/4 HD projectors or spend more on at least XGA resolution. My X1 still handles HD, but it can't reproduce the level of clarity that the higher resolution PJs can pump out.
If you watch primarily TV, then you're screwed no matter what. I've never seen normal TV look that good on a PJ.
If you watch primarily widescreen, then you might consider a widescreen format PJ. I stuck w/ the 4:3 projector in order to retain the full width of my screen, rather than having black bars inserted on either side during 4:3 material.
There is a lot to consider when making this type of choice. In my case, I had to take into consideration my ongoing basement finishing project with it's associated expenses. Given that and the fact that I could get an X1 for $900, made my mind up for me. However, in your situation, you may be willing to go to that next level, which is definitely attainable for sub-$2K (XGA and/or WXGA - Z2/L500U/PB6200). Regardless of the financial aspect of your decision, I would suggest that you focus more on things such as aspect ratio, primary source material, DLP vs LCD, etc. These things make the decision even harder, but it will help you to clarify what exactly you are looking for in a projector.