For a long time now, I am not satisfied with my sound, and because I have some spare money, I think it's time to buy my first pedal.

My gear: Ibanez RGA 32 with stock active pickups, Marshall MHZ 40c Haze

I am actually looking for a pedal which can give me the more subtle sound of early Thin Lizzy, but when pushed gives me a more modern distortion. I also like to play high gain stuff like Metallica of Van Halen.

Pedals I checked: cmatmods brownie, wampler pinnacle.

Where i'm not in the position to go to a shop and try them out, I would really appreciate some advice from you guys.

Your pickups would make the biggest difference.

The Haze is very old school Marshall rock tone, perfect for Thin Lizzy/VH. Your pickups are modern and have a high output, a Pearly Gates/JB would work well for those tones.
2002 PRS CE22
2013 G&L ASAT Deluxe
2009 Epiphone G-400 (SH-4)
Marshall JCM2000 DSL100
Krank 1980 Jr 20watt
Krank Rev 4x12 (eminence V12)
GFS Greenie/Digitech Bad Monkey
Morley Bad Horsie 2
MXR Smart Gate
You don't need a distortion pedal to get high gain with a tube amp. Look into overdrive pedals.

My advice is to set your overdrive channel on the Haze to get the Thin Lizzy-type sounds then use an OD pedal to boost that into a higher gain territory.

If you want to go from your clean channel directly to high gain, then you might want to get a good distortion pedal.
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