I use a home made one, just a 3Ah NiCd in series with an ammeter to the glow plug. The latest one uses 2 completely separate 1.2v cells, with a 3 position switch to select which cell to use. ie. Batt 1 - Off - Batt 2. This way there is almost no chance that both batteries will be flat on the starting line! The ammeter really lets you know what's going on when starting the DZ.

I haven't really had a problem without the delay... just check the meter, if it's high, activate the kill switch and start to clear out the excess fuel, then start normally.
We also use the TY1 glow clip, which is a push-on and turn type. It's the only one that lasts... without a remote glow.