Depends on what you mean by "2-way."
The Dynon Legacy units will display all HSI/flight instrument (e.g. TAS, Course, needles, GS) from the 480 and 430, and you can set the OBS course for Nav using the EFIS. Since they don't have moving map nor internal navigation capabilities, you must do your flight planning on the Garmin unit (which is just fine for many of us, making the Dynon the choice for the price-conscious). Dynon's new Skyview units have limited connectivity, serial only, but will have full integration later including all of the gee-whiz moving map and HITS, etc.
GRT integrates fine with both the 430/530 series and the 480, and I believe that MOST of the other EFISes do as well (but I'm not as familiar with them). Another interesting choice is the TruTrak EFIS. Think of that one as a top-notch experimental autopilot with a 6-pack and EMS as a "bonus." Coupled with a GNS 480, the TruTrak provides the best AP currently available with an interesting EFIS presentation for a good bang-for-the-buck.
The EFIS market is now very confusing because of the overlap of functionality between different pieces of your avionics. I recommend that people consider their entire SYSTEM, not just their EFIS, when purchasing. You may find that the gee-whiz features aren't really needed for your intended mission, or that you already have functionality in one unit (such as moving map on the Garmins) that you don't feel you need duplicated in an EFIS.
In the end, almost all of the available units are good; you just need to decide which one is right for you.