Every couple of years is pretty good. I was just worried that it would be every couple of months. It wouldn't be worth putting the time or cash into modding a system if the screen is going to need constant tlc.

I'm curious to try fixing these with a hot air technique, but I'm not overly optomistic about it working.

You definitely can't take any kind of direct heat to the ribbon cable or you will melt right through it, as evidenced.

It kind of depends. If you reflowed it well and managed to get the ribbon cable back to its original connectivity, in theory it's about as stable as it was from the factory. However, this is apparently not that stable. I wouldn't be surprised if a few years down the road you had to do it again. It also depends on the kinds of environmental stress the game boy is put through. I wouldn't be surprised if getting dropped a couple of times or leaving the game boy in a hot car could weaken the connection incrementally over time.

Is the vertical line fix a long lasting solution or do you end up having to open 'er up and reheat all the time? Or, another way, is it bailing water or plugging the hole?

From what I've read here, horizontal lines are nigh impossible to get rid of as opposed to vertical ones.

Nope. It's fucked. The connector on the right side of the screen is a different type of plastic, and if you apply heat to it, well, that happens.

Horizontal lines are a bitch. A word of advice when shopping around for another dmg, only purchase listings that include pictures of the screen as the last two I've purchased from eBay claimed to be in good and functional condition. When really I just wanted a front PCB and its plauged with lines vertical and 1 or 2 horizontal .

When I read the title of this thread I thought you were inferring to the ribbon cable that connects the front to the back PCB. In which case I can personally say they are transplantable. I removed the cable from the one on eBay and it completely fix an old front PCB I had laying around.

front and back boards are interchangeable

if you try this again definitely use a lower powered soldering iron

I didn't think so.. Darn.. I should be able to switch it out for another screen though right?

(The screen that came in it was from a DMG-07, while the motherboard was a DMG-03, so i'm pretty sure it's all cross-changeable)

I'm sorry to say it, but that's pretty much completely ruined.

by the looks of it - no.

Hello!
     Sorry to bug you all with such a ridiculous inquiry, but i recently toasted part of my ribbon cable trying to fix some horizontal lines after installing a backlight, and i think i may have just ruined my screen

     I suppose it wasn't the smartest thing to do, but i found a video (can't find the link again- sorry..) talking about how getting rid of the horizontal lines is almost identical to getting rid of the vertical ones- simply running a low powered soldering gun over top, resealing the contacts seems to do the trick, but my crummy hand-eye coordination lead to this (those with a faint heart may want to turn away)-
http://i.imgur.com/4itjb.jpg
and this..
http://i.imgur.com/PmbrN.jpg

TL;DR I'm pretty sure i ruined the screen- anyway i can turn this guy around? 

It's my first gameboy, and i'd hate to have it down for the count so soon..

Thanks in advance for any help!