I can pick either of them up for a pretty similar price (the yamaha is around $30 more.) But I'm not really sure which one is better. I'm looking for a mainly rock/metal sound.
They're both pretty sweet for what they are. If possible, play both of them, experiment with them and just pick whichever sounds better to you. If your buying online and that's not an option... a bit of a toss up. The vypyr is a little bit bigger, and has a bigger speaker, but those little Yamahas sound way better than they look like they would. The Vypyr can also be used a bass amp, and has acoustic amp models, for acoustic guitar. So, if you'd have any use for those, that would probably be a deal-maker there. The vypyr also has a looper built in, if you buy one of the Sanpera foot controllers for it.

I'd probably take the Vypyr myself, if those were my options.
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I have a THR10C and i think it's a fantastic little amp.

That said, for a 'rock/metal' sound then you may be a bit limited with the THR5, it only has a couple of lead and one high gain model built in. Plus you don't have the 5 presets on the THR5 so you won't be able to save any deep editing.

The reason i bought a THR is that you can set up a small number of really good sounds and the editing is simple and quick. It's also a good looking amp in a small package (so I'm allowed it in the living room ). If you want to fiddle with loads of different tones and effects then maybe it's not the best option.

If you could stretch your budget to a THR10X then it's certainly worth considering as i think its suits your description of 'rock/metal' much better and has those presets to tweak. otherwise, based purely on flexibility then the Vypyr is probably better.
i am not experienced with either, but to me a bigger speaker makes a big difference. its also nice the the vypyr has acoustic and bass capabilities. i liked the original vypyrs, haven't tried the new ones.
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youre just being a jerk man.

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