Andre,
I hope you are not on any kind of heart medications, are you? Because, TREMX can be very, very volatile. You did say you already have a 5% allocation to the more diversified EM fund, the Morgan Stanley Inst. Emerging Markets, MGEMX. I noticed it's top 25 holdings include some Russian stocks. So, this brings up the possibility that you may not be really increasing your diversification all that much by adding TREMX, because TREMX is 45% in Russia. You need to check MGEMX's latest fund report for a more detailed list of its holdings.
A couple of years ago TREMX did not have as much in Russia, and it had more in Eastern Europe. Today it's more like a Russian Lite Fund. Maybe one day it will diversify back in Eastern, Emerging Europe. If you do decide to add TREMX, I would go with no more than 3 - 5%. You also need to check your other funds' holdings for EM's. Even diversified Domestic funds can include a lot of EM lately.
Buckle Your Seat Belt!!
Coy
PS: Welcome to the T. Rowe Price Fund Family Forum!