I just had a quick look through all the posts on this topic and OMG the debate raaaaages on! 
The FDD8447 was just off the top of my head and because I've been using it. I never intended it to be the final resting point, the final decision for the mosfet, just as a guide. There are plenty of alternatives as have been suggested and some are far far cheaper (courtesy of wvmarle). I get FDD8447 direct for like 10c each but it can take a while to land them so locally sourced and under 50c is a good deal I'd say. And Mouser / Digikey are local to all of planet Earth.
Having said all that, I'd steer away from any mosfet that has sub 1V Vgst if the application is sensitive to power consumption. They make these low Vgst mosfets by building a bias into the gate by doping the material there and it often means a leaky fet by the time the gate threshold gets down to 1V or less.
Quick review of the PMV16XN: should switch in roughly half the times I indicated, approx 5degC temperature rise (steady state, no pcb / heatsink and 1A load) but beware, it has a maximum 12V Vgs and will be much more sensitive to ESD and comes in a SOT23 package which may be a bit fiddly to wire 'up in the air'. If you could put it on a pcb I'd say the part is not a bad fit for the project. Your call on installing a SOT23. There are TO220 options I am sure. Have a look through Digikey or some such and I'll be happy to review what you come up with if you like.
PE.