voxatc or other voice recognition atc addons for fsx?

I'd second what Murfman says about the frustration with MCE ATC comms. That's one advantage VoxATC has. The other thing is that unless you do pair MCE with one of the full ATC replacementes like Radar Contact or VoxATC

I was looking primarily just for the ability to talk to ATC, not particularly wanting more realistic behaviour, SIDS/STARS etc. I ran trials of It's Your Plane, MCE and VoxATC side by side. All of them offered that, plus other features of one sort or another.

It's Your Plane seemed OK, but the demo was so limited in what it could actually do, being restricted to the default Cessna and with pretty much all the features that I wanted to try out being disabled.

VoxATC gave far and away the best ATC experience - little extra things like being cleared to taxi across runways, or the ability to declare a mid air emergency. But I didn't like the very tight scripting you'd basically pick what you wanted to say from a menu and then it would display a script which you'd then have to read back. Not a great improvement over just picking the menu option, IMO. Also it disables any sort of traffic you may already have installed and instead creates its own AI traffic in a "bubble" around your aircraft. It will use AI aircraft that you have installed, so it'll use models and livery from a commercial AI package, just not the schedules. It seemed OK in practice, but I think I prefer the idea of properly scheduled AI flights. The price was a big negative point - the UK edition seemed to cost a fortune... and then on top of that you really need to think about investing in a number of quality SAPI5 voices, each of which are going to set you back £25-30.

MCE's primary focus is, like the name suggests, simulating a copilot and crew, though you can use it with only a subset of the options enabled (so you could turn off the copilot and the FSX interface command and just use it for ATC.) It's also designed to interface with the two main ground services add-ons (GSX and AES) as well as to either interface with, or at least operate seamlessly alongside, the big ATC replacements (Radar Contact, VoxATC, ProFlight Emulator) While price was a major factor, what eventually won me over was the flexibility of phrasing possible, which just felt a lot more natural that reading VoxATC's scripts. That's possibly a negative point, if you're wanting to use the sim to practice real world comms protocol and want to be punished for not using precisely correct phrasing, but for a casual leisure flyer like me it's a definite plus.

Since getting MCE I've also used the VoxScript feature to enhance the flight attendant's options, getting her to make various cabin announcements, which is almost like a whole extra add-on in itself.

So if your priority is better ATC, then MCE probably isn't what you're looking for. But if you just want to talk to default ATC in a fairly relaxed way, then I highly recommend it.

Dr V