is a center channel really necessary??

I agree with Shadorne that 4.1 is much preferrable to 2.1 for an enjoyable movie experience. I also agree that a poor mix down can make the dialogue hard to understand. But in my experience you don't need to spend a ton of money to get a pre/pro or receiver that will do a good job on the mixdown. My mid-range Pioneer Elite receiver does a fine job with the mix down. Not quite as good as my old Bel Canto Pre/Pro, but dialogue is always clear. Very important is to have good speakers of course.

I got rid of the center channel on my hybrid home theater (4.1) 2 channel (actualy 2.1) system -- using home theater bypass on preamp to connect a pre/pro to the stereo pre-amp.

Never looked back. Didn't miss it. Now that I have separated 2-channel listening from home theater (the systems are in separate rooms), I still don't use a center channel with the home theater systm and I still don't miss it. And I love the simplifcation in terms of fewer cables, less cabinets taking up space, etc.

However, I care more about music than movies. I think a real HT buff would never want to be without a center channel as it does create better separation of dialogue from background sounds and soundtrack. For me, that small (to me) benefit is not worth the extra hassle and cost. For you it might be.

I would start with spending more money on your L/R main speakers in a hybrid system. See how well it does on movies. Then if you really feel the need for a center, get one (hopefully with a trial period) and see how much it improves things. You may be delighted with it, or you may be delighted to skip it.

In my case I bought the center first, and then, realizing I didn't need/want it, I sold it. But at a substantial loss.

Good luck.