Well.
Iwill share my personal experience.
These are old engines, which we dont know how they were used before.
We always try to maintain it properly.
Spend alot of money just on maintainance.
But sometimes these engines give us tough time after maintained properly with company suggested parts/lubricants just because of previous experience.
I always maintained my Khyber with Suzuki genuine oils, my car was maintained From Suzuki 3s dealership.
But always failed to understand after the problems i faced.
Obviously its an old vehicle. It needs maintainance after the month end may be after or before.
I was always using 10w40 in my khyber.
But ithink the car was more happy in 20w50 (used by previous owner).
I always wanted to switch to 20w50. But due to non availability in Suzuki. I didnt go for it.
When came to plugs or plug wires, go for Genuine one, if i tell honestly, i have used almost all brands, believe me sab ek jaisey he hain. (Im sure alot of people will disagree with me, but my personal wxperience).
Sab ek time frame k baad khatam hojatay hain.
I always changed the plugs, and wires after 2nd oil change(6 months).
The plug wires brand is Sehwa i guess, you were talking about that.
I have used that one also. Im very much satisfied from sehwa. Will recommend to use.
Bht there are 2 types. Difference is the price. I got the expensive one. It serve me well.
So give some time, listen what experince persons saying.
You will learn alot.