Hey Chamai, I've got GAS real bad at the moment (picking up hopefully 4th MP2 and got a pair of MB1s and B500B), got told of a pair of vintage slant split stacks today, should I buy them (probably not, I don't need them, but tempted...). Probably the sensible think to say is consolidate what you have, but 2.2k isn't a bad price since it's pristine ?. But do you need it ? LOL, up to you my friend, it does seem a reasonable deal but will you use it ? I have my old Marshall '72 50w in the corner, I tried it once recently, was a real let down compared the MP1/2.
Headphones have their place, but I'm the same, I don't like using them unless I have to.