Is it necessary to use the same cable brand and model for bi-wiring??

What are you currently using for cables? You might want to look into or making your own set of jumpers instead of the jumper strips that came with your speakers. Also experiment the configuration on how to hook up cables with jumpers. There's plenty of info out there and Nordost Cables among others have their recommendations on it as well.

I wouldn't get too hung up on spending a ton of money on speaker cables for your Wharfedale's which I'm sure is a nice set of speakers. A very good and neutral biwire jumper by Clear Day Cables will work just fine. All cables are some sort of a tone control, even ultra expensive cables. I'm using WyWires Silvers with Clear Day Jumpers and they work just fine; I have a set of WyWires jumpers coming so using my Clear Days for now. I've not heard your Wharfedale's but I suspect my Aerial's dig a bit deeper and I don't feel not running two separate runs of speaker cables is going to change things much; they sound pretty darn good as is. The point is people with much larger speakers that have more top and bottom end get along just fine with a single run with jumpers. I'd recommend buying the best single run you can afford and use quality jumpers over two pairs for the same amount of money.