G'Day all,

My '02 Explorer is mostly garaged (only 60k klms to date) as I work out of the country, and only fire it up when home for a few days each month.
Most of the time, I disconnect the battery before I head off overseas, but occasionally I forget, and end up having to fork out bulk dollars for a new battery about twice a year.
My current battery is on trickle charge at the moment because of my recent lapse of memory, and I noticed an ad in the local rag for some Porta-Jump starter devices...going at 2 for $A100.00..bargain.
Porta-Jump Emergency Jump Starter
These little units sit in the glove box until needed, and would be ideal for this sort of situation I find myself in, but....
I bought 2 (the missus has an XR6, so she has one of these little beauties to go in her glove box, just as soon as her birthday rolls around in a week...or so,....I can never remember, but I love her to bits anyway, otherwise, why would I buy her something so special..?) but, I'm having second thoughts...about the Porta-Jump unit, not the missus, in that it runs at 30v and using a backflow type of charge to the battery through the power point/cigarette lighter connection, it will give the battery a quick-fix (like a major shot of juice) in 10 minutes..enough to kick the donk over.
The instructions suggest that all lights/radio etc must be off, but I'm a bit concerned about frying any of the computerized aspects of my car with this.
Has anyone used these units before in a similar situation, and would they consider them to be o.k. in this sort of situation...?
I shall leave the trickle charge going overnight this time, but I just know that the next time I head off overseas (3 days from now), I'm going to forget to unhook the battery, and then have to fork out $200 for a new battery again on my return.
This Porta-Jump unit seems like the answer to my dreams, but not if it's going to turn my electrics into scrap metal.
Appreciate any advice anyone might have here.
Cheers,