Not really...the Chelton stuff (now starting at $31K for 2 screens) won't talk or integrate to other EFIS's or MFD's...nor will Garmin, GRT, etc.. (the only people I know of that will work with others is XXX - as they have found a way to read the data streams from other EFIS's to creat a nice "slave" screen display for back seaters. (Oooops, perhaps I'm not supposed to leak that just yet so I won't)
Anyway, the G900X basically is the equivalent of 2 GNS-530's (high comm output of 16 watts), an MVP-50 engine monitor, a GTX-330 remote, and a PMA-8000B. So, you then take 2 WAAS GPS certified to the highest level and you're talking at a minimum dual 430W's or 530W's with your Chelton to be equivalent. The new Chelton GPS will be certified, but not available yet. Add to that it's price tag which likely be higher than a 430 anyway...and it's hard to see what is the best way to go. The Chelton will only take 1 GPS input, so now you're stuck doing something else with the 2nd unit, like installing yet another CDI that's not integrated to your EFIS. Everything ancillary is basically a wash (weather, autopilot, backups, etc..) so those don't necessarily add into the equation, except that with the G900X's we can package some of it together at a better deal then bying them alone.
Don't get me wrong...I still think the Chelton stuff is REALLY nice - and we're still selling it. It's just that if you're going to stack it up with dual everything else and add on the same goodies, you're pricing won't be far off. Now if you were to take an apples and oranges look at it by equipping the Chelton with differing units that aren't functionally 100% equivalent, then of course it's going to be cheaper. But, you can't use that comparision as apples to apples ...it's more budgetarily constrained/compared, not based on equal functionality. Lastly, one is certified and the other is not - which is hard to put a $$ figure on. They both have their benefits, but it's really hard to do an equal comparision when they are such different animals.
Each persons circumstances, budget, desires and flying will determine the best fit. For some it's going to be the G900X's, for others it'll be the Cheltons and for yet others it'll be something else like OP, GRT, AFS, etc.. There isn't a single system we deal with that I can consider perfect for all builders. It's a good thing we have so many choices!
Cheers,
Stein.