There's two sides of the coin when going direct, what the POD's putting out and what's done with that at the FOH.  A good sound engineer will help get the POD sounding great, but from your end, you'll need to get the tone sounding right at gigging volume levels.  Clean tones are more forgiving when you put some real volume behind them but the high gain tones can turn nasty.  First thing to try is backing off the gain on the high gain stuff, it can still sound killer with a lot less distortion in the tone.  If you're patches are not too FX heavy, try running a semi clean tone with the high gain tone, it's like tracking guitars in the studio.  Also play with the cab settings and if you want, try increasing the bias and/or reducing the master on the deep editing parameters for the modelled power amp.  The power amps are modelled at full bore which means the power amp and crossover distortion characteristics are very present in the amp tone.  That's fine if you play that particular real amp fully cranked, but if you don't then it's not going to sound the same.

Give those things a try and see how you go.

Cheers,

Crusty

I can vouch for the sound quality of the HD500 direct to desk. Just finished a N. American tour using it in that way and it sounded consistently great out front. Now...the sound *I* heard was entirely dependent on the stage monitors and the guy mixing them. Most times it sounded great but there were one or two gigs where the sound through the wedges was terrible because the wedges were terrible. So the best thing to do is stand out front and check your tone from the main PA. If it sounds fine there you might just have to put up with the sound you get on stage unless you can afford your own monitoring solution (some kind of powered full range speaker would be ideal).

This is assuming everything is set up right on your HD of course :)