Help on the end

[MuckerFish]

A little background, I'm usually fairly tight (VPIP 21%)and probably average aggressive. Been experimenting with a more laggy style, so I've seen more than my average share of pots when this hand came up. No good reads on villian, haven't seen him get out of line this session. In the past he hasn't been a superstar or anything.

.5/1
UTG (villian)(49.5) limps, hero UTG+1 (A [img]/images/graemlins/spade.gif[/img]K [img]/images/graemlins/diamond.gif[/img])raises to 5. All fold to villian who calls.
Flop K [img]/images/graemlins/heart.gif[/img] 5 [img]/images/graemlins/club.gif[/img] A [img]/images/graemlins/diamond.gif[/img]
villian checks, hero bets 8, villian calls
Turn 3 [img]/images/graemlins/heart.gif[/img]
check, hero bets 15, villian calls
river Q [img]/images/graemlins/spade.gif[/img]
villian checks, hero checks behind..

My question is this. I feel that I'm probably losing alot of value by checking behind on hands like this, but the smooth calls make me a little edgy. I guess I get a little worried that if I bet again I'm exposing myself to the possibility of someone coming over the top and putting me to a tough decision. (I know it doesn't matter here as much since the villian was short stacked, but if his stack was larger I get worried about committing my stack to a 2 pair type of hand) So my question is this- what kind of guidelines do you guys use when deciding to value bet your hand on the end, and how often do you back your bet up with your stack if someone comes over the top? What kind of hands will you defend? (Top two or higher, sets or higher, etc)
(i'm sorry if the question is a little vague, I'm sure it depends on reads and the like, but any guidance appreciated)

[unlucky513]

if that river Q makes villain's hand, i think he would lead out and bet it. i hate the check on the flop because like you said, you're losing out on getting more out. i'd make a 3/4 pot sized bet, hope for a call. if he does come over the top, i'm not sure what i'd do. probably cry and call.