[MarkGritter]

Generally, yes. You might get raised by an aggressive player, especially if he is drawing to a 7, but it is one of the cheap streets so you shouldn't mind too much. (Some players will bet or raise any one-card draw, even ones worse than yours.)

Suppose your opponent has 732xx to your 642xx. When you draw an 8, there are 13 good cards left for him to catch (3 8s, 3 6s, 4 5s, 3 4s) in a stub of 42 cards.

So, about (29/42)*(28/41) = 47% of the time he draws no good cards. The calculations for when he has a pat hand are longer, I used a tool to calculate it as 7.3%.

So, 47% of the time you definitely prefer a bet because you have an equity edge and don't want to give a free card. 7% of the time you will probably get raised and lose 1 small bet. The remaining 46% of the time he has also improved and probably has a better draw (or a worse one with an 87) but will be unlikely to raise you; one bet would go in anyway if you check/called, since he is certain to bet if improved. (Knowing your opponent helps here. If he autobets when you check you might get in a raise while ahead!)

The bet you get on this street may be the last opportunity for profit in the hand. If you make a pat hand on the next draw and place a big bet your opponent may have bricked again and fold leaving you only the ~3.5 BB in the pot. Make him pay to draw.

(It might be possible, in some cases, that you want to keep the pot smaller in order to give your opponent incorrect odds on the next street. Such situations generally only arise in multiway pots, though, you almost certainly do not want to give a free card here while drawing to a vulnerable hand.)