I have had a Malmer now for a little over a year and play it a lot. It's an awesome guitar with great tone and lots of balls when coupled with the correct amp settings.
To get a good shred tone you will need to use more distortion than you would with a humbucker since the pickups are very low output. They are on par with classic Strat singles (not the overwound type). Because they are the stacked DiMarzio's (HS3 brdige, YJMs mid and neck) people think they are humbckers in the classic sense, but they are not... and they are not high output. But they are hum free.
I haven't tried the capo, but I imagine you could get it to work ok but it would be a challenge if you were bending strings and doing other stuff while capoed. Capos generally clamp down on the fretboard at some point and that's what stabilizes them... this can't be done on a scalloped board.
The YJM in the middle is pretty useless tonewise. Like Yngwie, I never use it and have screwed down to the pickguard. Part of the problem is the way this pickup is EQ'ed... it's pretty dark, so there is almost no difference between it and the neck YJM despite the physical location. Strange, but true. In fact, all the pups are pretty dark which is what makes it sound so mean with a good distortion patch/setting.
Mine is a maple board with the vintage white (or pee-pee yellow, as I call it
). Rosewood boards are easier to maintenance when it comes time to re-fret and the tone is slightly different... but unless you're Eric Johnson with neurosis of the ear and can claim to hear tonal differences between specks of dust resting on your headstock, then just think of rosewood or maple as aesthetic choices. I preferred the classic Malmsteen vintage white/maple combo because he is most readily identified with this particular config.
The guitar itself is made in the Custom Shop, not on the assembly line. The body is routed for singles only, no huge "swimming pool" route for humbuckers which I am convinced makes the guitar sound even better. I have two other Strats (a Custom Shop and a Deluxe). The CS, like the Malmer, is single routed only and the Deluxe is humbucker routed. All three are made from the same wood (Alder) and they both smoke the Deluxe when played unplugged. Of course, the vintage tremolo helps a bunch with tone coupling over the modern trem of the Deluxe, as well. The CS and Malmsteen almost acheive acoustic loudeness when played sans amp!
All in all, a great guitar... I highly recommend it.