First I suggest you don't do it and invest a little more cheese on a better iron.
I have owned a couple in the past and they have been okay. The problem with them is the tips suck. If you don't plan on doing a lot of DIY you should be fine as long as you take care of it. As for size the smaller ones will be fine for phone wires but for larger stuff you will want something with more power. Stay away from guns.
I purchased a Xytronic as I iron for here in Iraq and I have had really good luck with it. It also uses Hakko tips.