RE: Best glow driver?
As Red B. from Sweden was asking, this (and some other glow drivers that are in the upper price range) provide a variable current to the plug so that the plug heat remains the same regardless of amount temperature, raw plug full of fuel etc. If you use a normal glow clip w/battery it's gonna start glowing immideately when its connected. That's not good for the plug, and you get the problem of backfiring. With these new generation of non-knocking heaters you can start spinning the engine before it starts giving current to the plug, eliminating the backfiring problem.
The driver I use is 1295,- NOK which is equivalent to 240 USD. It sounds expensive but the currency rate is very much in favour of NOK right now. A few years ago it would have been a $100 less but yes it is not cheap.