What Soldering Iron do you use?

[JThiessen]

I have three - a Weller SP40l iron that burn tips like crazy, and then othertimes wouldnt burn its way through toilet paper. I also have a Weller Universal 140/100 gun that I've used quite often in the last year. But it too has recently started operating erratically. Sometimes it heats, sometimes it doesnt. The handle itself has started to warm up after being plugged in too long.

Why do they say not to use a gun for soldering batteries? Is it because they typically put out too much heat?

Second question: Is that Hako sold anywhere outside the RC hobby world (ie. without the flame job?).