So I know that the best way to buy a guitar amp is to try them out at a store, which I am going to do, but I would like some suggestions first.

My guitar is an ESP with active EMGs. I also have a Line 6 POD x3 Live, but I may not use it very much if I get a good enough amp. I play all kinds of metal: metalcore, death metal, groove metal, stuff like that, but i also play some rock and some clean stuff as well. I play music by bands like August Burns Red, After the Burial, The Devil Wears Prada, Lamb of God, Meshuggah, Amon Amarth, Pearl Jam, Nirvana, Stone Temple Pilots, Led Zeppelin, stuff like that.

My price range is anywhere between 0-$500. I can go a little higher, but up to $700 is pushing it. I don't care if it is tube or not, as long as it sounds good on both a lead and clean channel.

If you need any more info, just let me know. Any help is appreciated. Thank you!
Used 6505+ 112 & a Boss NS-2 should run you that much.

Alternatively you could get a Bugera 6262. Just make sure you have enough left over for a noise gate, if you don't already have one.
Spin 'round carousel when your horse isn't screwed in.

My band:
Fractured Instinct
(For fans of Death/Groove/Prog Metal)

Ibanez RGA42E
Ibanez S420
LTD H-301
Ibanez RG520
Peavey Predator USA
Douglas Grendel 725
Line 6 Pod HD500X
Yeah, the 6505 112 Combo is the best place to start.

Not sure if a Blackstar HT-40 falls in that range down your end, but it does metal, but has a bit more versatility for classic stuff with a vintage voicing option as well as UK and US voicing options, and supposedly has better cleans than the 6505. The cleans on the 6505 are decent I guess, but not the best from what I've heard.

As you mainly play metal, the 6505 is a good bet. It's a legendary metal amp and at that price point, you're getting good tone for most of what you play.
6505 is a good choice, but a XXX or Ultra would be better for cleans and lower gain stuff, both can be had easily for <$500.
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The vision never dies, life's a neverending wheel.
You could also get the older 5150 combo 212 for cheaper than the 6505.
I ended up getting a 1x12 valveking and an orange 1x12 cab. Was a little pricey but was definitely worth it.
If you're patient and go through Craigslist, you can find used Peavey 5150s for super cheap. I found mine for 300$. Amazing deal. However, the clean on this amp is non existent as it has a Lead and Rhythm channel.

I'm a fan of the B-52 At-100. It has a lot of gain on tap and a really nice clean channel. You can find them used for really cheap too. It's not uncommon to find them for under $300.
Ahk, Valvekings seem to be popular budget amps around here and can sound great with a few mods. There's a thread around here you can search for.

How's the Orange 112 btw? I've heard mixed things about them; I know the PPC 212 and 412 are fantastic. If it's not too late, I've heard great things about Jet City 112 cabs.