I just got my 139XLR repaired today. The AM side was not working, and was easily repaired. The tech I used has been around for decades, and said that it was a great rig, as others have said here... that it is easily modified. He also said that it comes with a built in speech processor. It really talks loud both on AM and SSB, even with a stock mic. I don't tend to have my rigs cranked to the max, but it is dead keying 2.5 watts and swinging to 10 on AM, and doing close to 18 watts on SSB. The receiver works fantastic, and I don't believe mine has had any mods or "super ears" done to it.
I can't knock the 142GTL either. The looks are a little nicer/fancier, and it has a solid, time tested board. You hear a lot of them on DX, and they always sound good.
To me, either one makes a great base rig for a very reasonable price.
73,
RT307