hang in there, man.  the secret is EQ'ing.  The Mark V uses pre-gain EQ'ing to adjust your distortion tone.  Try setting its bass knob all the way up, and mid, treble, and presence knobs all the way down.  I bet your tone gets muddy.  The 5 band graphic EQ is what EQ's your post distortion tone - turning up the bass there won't make your tone muddy, just bass heavy.  There's a quick primer on pre-gain vs. post-gain EQ'ing.  This will work the same way on the Pod HD, only you don't get the simple bass, mid, treble, presence knobs.  But on the other hand, the Pod has a bunch of different amp models, so you can get a much wider variety of tones.

Just learn how to use the parametric EQ effect on the Pod HD.  It gives you the most control.  Forget about the others for now.

"lows" is a shelf EQ.  It boosts or cuts all frequencies above below I think 240 HZ.  Boosting it will make your tone sound like this (in the following diagram the amplitude or volume is on the y axis and frequency is on the x axis):

___

   \__________

Cutting would look like:

    __________

___/

50% is neutral.  100% is max boost.  0% is max cut.

"highs" works the same way but its cutoff frequency is at 1.5 kHZ (1500 HZ).  Boosting:

          ____

_________/

cutting:

_________

         \____

So you consider "lows" the same as your bass knob and "highs" the same as your treble and presence knobs, more or less.

The frequency, Q, and gain controls all work together as a peak/valley EQ.  Frequency defines the location on the frequency spectrum where the apex of the cut/boost will occur.  Q defines how narrow or wide the boost/cut is.  Gain defines whether you are cutting or boosting and how strong you are doing so.

So turning up the gain with frequency at 50% would look like this:

      _

_____/ \______

Moving frequency up to 70% would look like this:

         _

________/ \___

Turning down the Q would look like this:

       _____

______/     \_

Turning up the Q:

_________/\___

Just play with it until you can really hear how these controls shape the tone.  When you change settings, try to toggle the effect off, play a little and turn it back on.  When you change settings you might be subconsciously thinking it's doing something else because of the comparable tone at the old settings.

So if I'm trying to match my tone's EQ to something else, I'll start by getting a reference clip and getting my tone at the same volume as that clip.  then i'll try to determine what the difference is in very basic terms - does it have more bass or less.  more treble or less.  I'll see if adjusting the "lows" or "highs" gets me closer.  Everything in the middle I'll have to adjust using the peak/valley part of the EQ.  I'll set the Q up to like 85%, so that I can hear clearly how it's changing my tone, and crank up the gain.  Then I'll sweep the frequency control to find the spot where it feels like i need to adjust.  i'll lower the Q to widen that spot until it feels like the size of the boost/cut i need, then adjust the gain to get it as close as I can.

The more you mess with it, the more you'll understand what the hell I'm talking about.