Crafty is a perfectly decent engine.  Not quite as strong as Fritz, Shredder etc. but certainly strong enough to kick my butt all over the board! 

I'm sure there probably are but all-in-all I imagine it is less liekyl to fall into the sort of problems that afflicted Fritz in Game 3 of its recent match with Kasparov, where it just didn't know how to handle the interlocking pawn chains and never got any play going on the kingside where it had more space.  Kasparov just steamrollered the machine on the queenside without it getting a whiff of counterplay.  I can't say for sure, but I can't imagine Hiarcs having the same problem.

On the other hand in hand-to-hand combat, give me Fritz any time - it just seems to see further for some reason.

You really can't do better than Fritz, but Shredder, Junior, Hiarcs or Tiger are all perfectly good alternatives.  If you can spare the cash it might be worth investing on a coupel of programs (I use Fritz and Hiarcs more or less interchangeably) so that I can get 'second opinions'.
For basic tactics they all do the job, but they will disagree quite markedly about the evaluation of some positions.  I still think Fritz is the leader, but there are some positions it just doesn't 'get' at all, and for those, Hiarcs is a good alternative.