Hmmmmmm... That's a tough one.
Honestly, I'd say that the US side of the Schizo switch on my Hellhound sounds somewhat like more of a BF/SF amp. It's got punch similar to a Deluxe, while maintaining a nice smoothness on sustained notes not unlike a Bassman.
I spend most of my time on the UK side however, as I'm mostly a British-toned man. While some people really despise Marshall cleans, I love 'em. They're the most gutsy cleans on the planet - just not really suited to Beatlesesque jangle. That being said, the clean tones in UK mode are more flexible that those on my JCM800. There's a lot more bounciness and jangle to the Hellhound than the Marshall. In fact, when my new 4x12 cab comes in, I plan to use my Hellhound (I have the head version) on my 2x12 and my Marshall on a 4x12 for A/B/Y clean/dirty/both tones. I'd compare the cleans on the UK side to a blend of Marshall, Vox, and Hiwatt, but I think you might actually be able to squeeze tweedish tones out of ther UK mode if you play with the eq a bit.
The gain knob is a nice one. In fact, I'd say that where the Hellhound excels is in the "in-between" tones. Crank the knob all the way up, and you've got a good amount of gain, but the guitar will always shine through - you don't need to worry about that. In fact, in the UK mode, with a spoonfull of gain is where you might find the tweediest of sounds in the amp.
I happen to occasionally use both of the pedals you mentioned, and if you need a fully-saturated tone, you can hit it with either one, and get a pretty mean grind. It reacts very well to pedals, and especially to clean boosts. I played in a semi-hardcore band for awhile with nothing but my Hellhound and a BD-2 to kick it up a notch.
Whether it's for you or not is a tough call. I know that I love mine, and up 'till now whenever I've gotten a new amp, I've sold the old one (poor college student dontcha know?) but when my Marshall showed up, I knew I was keeping the Hellhound.
Last note. I tried the combo version during my search, and it's pretty nice too. I just needed more of a closed-back tone so I went with the head. I might venture to guess that the open-backed combo might even lend a little more jangle and bounce to the cleans on the UK side.
Best of luck. If there's anything else I can tell you about it, feel free to PM or E-mail me.
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