It's impossible to find actual bass players where I live, so I'm currently playing bass in a metallic hardcore/grindcore band instead of guitar. I've been on the internet all day researching bass heads, and the two I've narrowed it down to are the Gallien Krueger MB500 and the Ampeg PF 500.

Which would be best for the style of music I'm playing?
(Think bands like Converge, KEN Mode, Gaza, ect)

Or, do you have any suggestions for amps that would work for this style of music?

I'm looking to spend around $400-$600 (max), because I also have to pick up a bass because I'd like to stop borrowing equipment.

I already have a Boss ODB-3 pedal that I've been using, so I don't necessarily need a ton of extra distortion.

I'll be going to try both tomorrow before I make a decision.

Any input is appreciated.
I've played the GK MB500, and it is a fantastic amp in a tiny package. There are a lot of good tones to be had from one, so I believe that it will suit you well. It has the power to be heard in a hradcore band, unless your guitarist(s) is using something along the lines of a 100-watt Marshall stack.

What cabinet will you run it through?
"Maybe this world is another planet's hell?" - Aldous Huxley
The GK amps are renowned (or notorious, depending on your perspective) for having a very coloured tone. Because of this, I'd recommend trying one before you buy, they can be a bit marmite. The Ampeg PF-500 is a decent head, again somewhat coloured (but in a way that seems to offend fewer people), although there have been several reports of QC issues with them. I've used one at a gig before and loved the tone, but I've read several accounts of them breaking not long after being purchased. I'm sure these are still minority incidents, but I wouldn't be comfortable gigging one without a back-up personally, at least for the first few months.
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