don't know about the OP, but I don't like the look of TD at all. For me, it wasn't very intuitive. Also, having to spend $20 on functionality that was supposed to be built in isn't going to happen. The Exchange implementation as it is now is fine for me, as I don't have any issues with policy enforcement or anything on our system. Yes, I want signature support and having to go into the corporate calendar to accept appointments is a little annoying, but not enough that I need to spend $20 on an app just for a few little things.
i suppose it could look a little more...industrial?...but the functionality it provides overshadows any issues with looks by far, in my book. as for intuitiveness, it's easier to setup than the native email/exchange and everything else seems pretty straight forward...to me at least. activesync push works flawlessly, you can choose which folders you want to keep synced, show received and sent messages in one view (had my bb set up like this), meeting requests, calendar sync, contacts sync, tasks sync, signatures, custom alerts, change font sizes, etc.
as for the cost, i was lucky enough to purchase this when it was $10 bucks so i understand those who were chafed when they raised the price to $20. but that said, you can't blame the developer for charging for an application that provides better and more extensive functionality than google provided standard. it would be nice if google included that functionality in android, but they didn't. plus we don't know when or if they will improve it to the level of what an app like touchdown does.
coming from a blackberry that i relied on heavily for work email/outlook (exchange) integration this application made the transition to android so much easier. i tried the native email app for a couple days and really disliked it. it's far too spartan for my needs. and to be honest, although the droid is much better overall than the blackberry i had i might have been forced to go back to blackberry if it weren't for touchdown.
to each their own though. the native email app cuts it for some users, in my case it was dreadful though. i do hope they improve the native email/exchange integration. this is one area where android really lacks for business users on exchange imo.