Common spot, BB w garbage, limped, hit bottom pair

[Antinome]

Poker Stars - No Limit Hold'em Cash Game - $0.10/$0.25 Blinds - 4 Players - (LegoPoker HH Converter)

SB: $14.65
Hero (BB): $31.70
UTG: $38.10
BTN: $24.05

Preflop: Hero is dealt 4[img]/images/graemlins/diamond.gif[/img] 8[img]/images/graemlins/heart.gif[/img] (4 Players)
UTG folds, BTN calls $0.25, SB folds, Hero checks

Flop: ($0.60) A[img]/images/graemlins/spade.gif[/img] 6[img]/images/graemlins/club.gif[/img] 4[img]/images/graemlins/heart.gif[/img] (2 Players)

I've been going for a checkdown in these spots. Is that best?

if villain only hits 1/3 of flops, it seems like if we bet 2BB in these spots we should show an immediate profit. Thoughts?