I'm using a 36" JVC crt that I grabbed on craigslist.  Bigger than anything I had in my youth.  Best part, no messing with latency issues, conversion problems, etc.  I retain the transparancy effects and beautiful scanlines!  I've done the emulation route, and the retron with HDMI is nice for the quick easy hookup, there is a difference playing a game emulated.  You may not notice right away, but play a game like Galaga emulated and then on original hardware.  You will notice.  I do a lot of restoration in the arcad scene, and emulation boards are all the rage right now.  they are perfectly find for most people, but I have played original boards far too long that I can tell that the play is just off a bit in emulated ones.