I actually brought 2 3gs phones with me last trip.
I thik the key is be nonchalant. Its all good.
Granted these were used. People had asked me to get them , but they punked out when it was time to pay. I gave one away , and I have the other one in my desk drawer.
I always bring those things back that i cant find here . Mostly hardware items. I also bring back a few thinkpads that my buddy , who is a tech soehow accumulates. I prize them. I brought them both in my carry on and in my laptop case . Never had a problem, they never asked me anything more than to put all the luggage on the xray belt and that was that. Gace them a good morning , and a hava a nice day , and didnt look back