I've found a couple tricks that seem to help with those double sided boards that have solder pads on both sides and don't want to "give up" the solder stuck inside them, especially MXRs.
***Note: I use desoldering braid, not a sucker.***
1) Before desoldering, try
adding some fresh solder into the joint. Apply liberally. Heat up the new solder with the old (within reason of course. Don't burn the crap out of your components or the pad.) Then let it cool. Heat it up again and try desoldering. That usually does the trick for me.
2) Still not getting all the solder out? Get a third hand and a toothpick or fine soldering tool/pick. Now heat up your pad again and gently stick the toothpick or tool through the hole to clean it out. Just be careful that you don't damage the pad. (A soldering tool looks pretty much like an awl or dental pick with a long fine point. A third hand can be: a person, clamp, or a soldering station.)
If anyone else knows any good tricks for this, post it!
