I've owned the 7008 for four years and am happy with the amp.
But it is not possible for me to compare it to other amps, since I have not tried any others in my system. So I don't think I can be much help.
Personally, I think the 7008 is now overpriced. There is one for sale right now here on audiogon by an authorized dealer, at a pretty decent price, for less than I paid for my dealer demo 4 years ago. But no way would I spend the full retail price of almost $9,000 for this amp. (Even the Pass Labs INT-150 has a lower MSRP. OTOH, more expensive integrateds include the Boulder 865 at $12,000. But with the decline of the dollar I suspect that you get more for your $12,000 with the Boulder than $9,000 for the mbl.)
The 7008 is convenient. It is perhaps the main reason I bought it. It does have a balanced input (and three RCA), but you have to pay extra if you want a second balanced input. I like the fact that it has a headphone output on the front of the unit. IMO, more high-end integrateds and pre-amps should come with a headphone output. It's essential for apartment dwellers like me.
There is a review of the 7008 here (may take a few moments to load) which can describe the characteristics of the amp better than I could.
http://www.stereotimes.com/amp051905.shtmlI'll say this. One night my next door neighbors were partying too loud too late, so being a little drunk myself, I thought I'd blow 'em out. I put on "Stairway to Heaven" and turned the volume up full blast on my Krell Resolution 3 speakers. It was UNBELIEVABLY loud. But not one indication of distortion.
Having standmounted speakers, I can't give a definitive evaluation about bass performance, but I have no complaints! I think that my system sounds just great. But how much to attribute to the source, the amp, and the speakers, I just don't know. Overall the tonal accuracy seems pretty fine to me, both on rock n' roll and female vocals.
I don't know the specific differences between the 7006 and 7008. Mbl is rather tight-lipped about their circuit design. I remember they published a white paper about one of their amps once, which I no longer see on their website, and in describing their top-of-the-line amp now, they give a few technical features, then say "Technical secrets that we would rather keep to ourselves."
If you are looking for a high-end integrated with convenient features like remote control, headphone output, and HT bypass, and the reliability and low maintenance of solid state electronics, I think the mbl is a fine choice.