funkadelic wrote:
Overdrive will be generated by pedals.
Unless you really like high gain, that will all change when you get a proper valve amp.
The dynamics of a clean boost pedal into a dirty valve amp VS. overdrive pedals into a clean amp just cannot be replicated IMO. If you like using picking dynamics and doing things like changing between your pick and your fingers to get different sounds, you may find that the overdrive you get from the amp itself far surpasses the overdrive you may get from pedals.
Spend some time with the following very complicated setup:
GUITAR > CABLE > AMP
You will start to see how a valve amp can give you very good overdrive tones. You may even sell some pedals.
As for choosing between the amps, I found that the blackstar HT series amps have far too much gain - I guess they tried to cater for all types of people - and this left me wanting when it came to light overdrive sounds. These modern amps rely far too much on preamp distortion to get their sound and you end up losing a lot of dynamics that would usually come from the power amp tubes. If you are drawn to the ISF function of the blackstar amps to get UK or US sounds, you would be much better off learning more about properly setting your EQ.
You mentioned playing mostly clean, which I assume means that you do not play high gain stuff. In that case I would rather get a simplistic amp (ie the one with the fewest marketing crud and the most clean headroom) and shape your tone using pedals. Just remember that clean headroom usually means you will only get amp overdrive at very high volumes - just ask the fender guys. In that case you will probably be stuck with using pedals...