They basically stop your fingers tips rubbing on the finger board when playing, meaning that bends and vibrato become a little easier. Yep, you have to be a little lighter with your touch, otherwise your notes are going to be out by a few micro tones. you can get some great bends on them though! They let you get right under the string.
Malmsteen may be a dick, but ive never heard anyone that can make a strat sound like his. Personality aside (bearing in mind im talking about general consensus, as ive never met the guy!) i think hes awesome.
All of Malmsteens frets are scalloped, but vve played a few guitars where only certain frets are scalloped. Some of the steve Vai Jems being a good example, with only the last 4.
I suggest you play it before you buy it. It will feel different, but mainly just because your not used to it.
Alternatively, just get better so that your fingers dont rub on the finger board
