NEX-3 or NEX-5?

[Vivek]

All the metal parts in the NEX-5 body acts as a heatsink (for the sensor, i presume). The metal mount heats up noticeably after being in use for a while.

So, I would suggest the '5.

 

[LizaWitz]

@Anselgrey23 -- The NEX 5 has an IR remote to trigger it. Maybe in the future, or maybe one of the sony remotes, allows for a bulb function.

Personally, the only thing I'm a little worried about is whether I'll be able to get an intervalometer setup. but I found that there's an iPhone IR accessory, so if necessary I can write my own intervalometer app.

@Vivek-- Interesting news.