ok,well since you mentioned liking the Purplexi amp youtube video with the Friedman KS mod,i figured i'd respond since the amp was mine when i made that video clip.Dave Friedman's mods sound EXCELLENT at even the lowest,bedroom volumes.there's quite a few guys on the forum that own a Friedman-modded amp and can attest to this(i.e. LpFreak,232cap,Tonmazz and Marshall Law to name a few of those guys

)...the Kitchen Sink mod with the SATURATION switch is all you'd ever need to cover every Marshall tone out there,from classic rock to 80's metal and more.the SATURATION switch feature is Dave Friedman's version of the classic jose-high mod(like the cameron jose mod).it's a $50 addtl fee to have this circuit/mod added to an amp that Dave's modding for ya and it's a NO-BRAINER since,with a flick of a toggle switch(or you can have it set-up on a push/pull pot) you get that very saturated,grinding,pissed-off high gain "metal" tone and all for such a cheap price.last i heard,Friedman was charging $500 for ONE mod,$600 for TWO mods or $700 for ALL three mods(aka KITCHEN SINK).if you didnt want to spend the full amount for a KS mod,you could get ONE mod for $500,then add the SAT switch for $50 and between say getting the BROWN EYE mod as your one mod and the saturation circuit,that'll get you tones from AC/c to Metallica - NO problem!!! ...plus Dave's turn-around times are very good...
...on a separate note,i'm told Fortin does great work too and his Cali mod does sound excellent based off the clips that i have heard.Splawns are great amps too,as i've owned 3 of them,but i dont think they will satisfy that cameron jose-hg/ccv tone quest that you desire and i do agree that they are not very good at lower,bedroom volumes...just my 3 cents