Pinned straw:
I think Transurban is a perfectly good income investment @Parko5
The 4.8% yield is about on par with a term deposit, but as you rightly point out they still have decent growth options -- even if you just assume inflation-linked toll rises.
They are, of course, heavily geared, but this is secured against real and valuable assets, reasonably long dated and they have very reliable revenues. They didnt have any real issues during the GFC, for example.
I tend to think the easiest way to value these kind of assets is to add the current yield to the expected average annual increase in the dividend -- so as a rough thumb suck you could probably be reasonably confident in a 9-10% total average annual return (assuming reinvestment) or a near 5% yield where the income stream grows at 3-5%pa
Maybe it wont shoot the lights out, but it'd provide a good income stream over time.