If you need a good electrician, I can refer you to two. PM and I will get their numbers for you.
They are both excellent, and I have worked with both.
They are not cheapos however.
Knob and tube is funny stuff. I had it in my house, and still do in one room, but I rewired my house myself (after one of the above electricians put a new panel in for me.)
The problem with knob and tube are as follows:
1. No ground wire.
2. Insulation that tends to crack or be brittle over the ages.
3. Previous owners who fuck with it.
4. Connections in the walls with hockey stick tape.
5. Overloaded circuits (4 circuits for an entire house.)
6. Burned up or missing insulation where there are ceiling light fixtures.
7. Impossible to expand upon.
I know, I had all of the above.
The actual knobs and tubes are a great idea though. Too bad you can't use them with Romex.
I like to call knob and tube "barbeque starter" wiring.
But I would bet that 85% of homes originally wired with knob and tube in the city of toronto are still using some, or more likely all of it.
All of my neighbour's are still using it and their reactions to me getting rid of mine vary from mild agreement (but too lazy and cheap to follow suit) to denial that there is any need to rewire.
One of my best friend's had her house actually catch on fire due to an electrical fire (though strangely, it was a newer wire and not the knob and tube wiring). When she bought the place I told her to rewire it, the wiring was/is a DISASTER. Even offered to help. But she just figured that "everyone else has knob and tube" so she left it. Then it caught on fire and destroyed one room and damaged the rooms below. You'd think she would rewire the entire house then wouldn't you.
Nope.
It was rewire the house, or travel for the summer (she's a teacher).
Travelling won out. (Figures she is a teacher I know.)
How she sleeps, I don't know.
As an interesting aside, another friend of mine is right into antique ham radios and he actually wants all the old ceramic knobs and tubes and cloth insulated wire that I can give him. Maybe there is a market for this dusty old stuff on ebay, I dunno.