Roscoe, that's a great service story so far.
In re: issues,
In Canada they've been on sale for a lot longer than in the US. Even longer in Europe. Let's keep that in mind too.
There are two dealers I know of in Canada (there may be more now), one of which is somewhat local to me. It's a nice store run by a guy who has a lot of experience in electronics and amp repair. I can't recall if he would work on MB or not in case of failure - I know he's "authorized" to toggle the jumpers at least - but he has every confidence in them, uses them himself, and reported zero failures when I asked him several months ago. And he's sold a lot - he can seldom keep them in stock, especially now that so much product for North America is diverted to the States.
One of those rigs was sold to a major backline rentals company for major label acts and it still works fine. I can't say for sure it's never required repair, but I still see it in use so it can't be a hassle for them to provide it since in part their reputation and future repeat business is on the line (the backline rental company, I mean).
I've run into a surprising number of players - pros - that have MB amps and combos and they've all totally raved about them and they sound great. When I ask, I expect them to say something like "yeah, it's ok - I like that it's tiny ..." and instead the answers have all been a very loud and enthusiastic "I love it !" or "Markbass ####### rocks man !!!". Again, actual pros gigging on DB and electric. They've never heard of Talkbass so they can't be here to report, but some do exist. And I can't have run into the only ones out there. Again, I'm very surprised how many I see in use.
I like mine more all the time, and not just for the size/weight, and it runs daily for hours and works fine after ... must be 6 months now. Last night I used my Scout and man do I wish I'd brought my LMII/Schroeder setup instead.
I've owned and gigged all the competitors (except Epifani) of similar specs mentioned so far in this thread and I prefer the MB on sound and function alone. The price and size/weight puts it waaaay over the top. I find more than a few gigging pros on TB, and elsewhere, that feel the same way. The competitors will have to pray hard that MB failures become an epidemic or that GC goes bankrupt becuase that's really their only hope of gaining the upper hand at this point, IMO.
As Brad said though, everyone should ideally have a backup. The fact that someone local can maybe fix an amp does you no good on the gig. It's like those ###### Monster Cables. They fail a lot and you can brag about having had 3 replaced for "free" so far after driving across town for an hour, but what good is that on a gig?
Solution - buy 2 Markbass amps for the price of one of most of their competitors. Heck, get an LMII and a used Walkabout and have a very wide variety of tones, a backup, and still spend about the same as most other amps of similar specs cost and still be carrying no more weight than those and only slightly more bulk.
That's good sense and that's good practical math.