After 24 hours I'm very happy with my purchase. It's taken a little time working out how to use it without wishing I was keeping my M13, but I have it all worked out now. I've also tried out the PC editing software which is a great way of creating tones (rather than crouching over the hardware).

The way I'm already preferring to use the PC edit software is to create a patch that's in the ballpark of what I'm after, all the FX in the right places, choice of amp etc. then pass it over to the hardware for actually playing/tweaking.

On the unit itself I've created three separate setlists. The first is a selection of tones that use the preamp versions of the amp models. I'm using the pre-amp versions because for this setlist the idea is to use the HD500 plugged into the FX Return of my Bugera V22 tube amp (EL84).

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The second setlist is exactly the same patches as the first one but using the full rather than preamp versions of the amp models. This setlist is for using with headphones on. I've tried the pre-amp and regular versions straight into my Bugera and both sound good (in addition there's a global setting to tell the unit you're running into a poweramp) I decided to do things this way just as there's so much storage space I may as well use it.

My final setlist (so far) is titled M13. Here I've set up three different patches - clean, crunch and lead. None of these feature any amp modelling at all. Each features eight FX units and each makes use of the HD500's FX Loop after the first four FX. I can then use this setlist and the HD500 just as I did my M13, as purely a stompbox modeller setup with my amp using the four cable method.

Even better, this M13 setup allows me to use eight simultaneous FX compared to four on the real M13. Another benefit compared to the real M13 is the toe-switch on the expression pedal for switching between wah and volume - you can't do this on an M13. The FX Loop also means I can use my HT Dual and Bluesbreaker II pedal in exactly the same way as I did with my M13. The ONLY limitation to using the HD500 this way compared to the real M13 is that I have access to eight FX per scene compared to 12, however the ability to use all of these at once outweighs this. And of course I can easily switch between various scenes to give me access to just as many effects.

Turning to the audio quality itself. The FX are all the same as the M13, the HD500 features over 100 - which you'll have if you've got an M13 with the latest firmware. I'm already a great fan of these effects and I'm delighted to have the whole set again in a new box of tricks. Doesn't feel like I'm giving anything up now I've worked out how to set up the device as a pseudo M13.

Finally and most importantly we come to the amp models. Even with just 16 compared to the 70+ in the POD X3 I still haven't had chance to explore all of them yet. Those I have tried I've been very impressed by. Certainly A/B with the real tube preamp of my Bugera V22 I cannot really find any dynamic or quality difference (obviously they don't sound exactly the same as there's no V22 model).

The Plexi and the Park are my favourites so far. I was really hoping the Plexi would be as good as the one in Guitar Rig Pro 4 and it is. Line6 has been much more restrained than usual and the Plexi model can't be turned into a metal chugger just by turning the drive up - you have to use distortion models before it. The Park has that characteristic Marshall midrange bark that so many of us love.

I was expecting the Divided by 13 model to be pretty good - it's one of the best things about the new Spider Valve MKII. The HD500 version is even better. One of the faults of Line6 modelling in the past is the lack of functionality that the real amps themselves have. So each model might sound a bit like the real thing - but it has a drive, bass, mid, treble, presence and volume whether the real amp has those or not.

The HD500 gives a more realistic approach (though the manual admits it still adds tone stacks to amps that may have only just had a volume knob and nowt else). The Divided by 13 model has two channels - the volume for the clean channel is on the HD500 driver pot, the volume for the drive channel is on the HD500 bass pot. So you can blend the channels and create some beautifully deep crunchy tones. The mid pod functions as a tone cut, just as the real model does. Similarly the Vox model features the kind of tone cut control previous Pods haven't bothered with.

Obviously it's still early days in using the HD500 but I'm very happy so far. Sounds great, has loads of great features (so I did have to actually download and read the full advanced manual) and now I've figured it all out it really does seem it does exactly what I want and replaces two boxes with one.