i just wanted to point out the usefulness of reapers as a lategame harrasment unit
1. the standart TvP for most players revolves around huge amounts of techlab barracks with mass marauder production. meaning in a usual +3 bases situation you have around 8 to 12 barracks anyway so throwing in a round of reapers is technically possible.
2. the mass rax play relies on fast uprgades, those work for reapers aswell
3. speedreapers are faster than any protoss unit except the fenix
4. a group of 12 reapers with +3 attack 2 shots any protoss tech or production structure
5. reapers jump cliffs
6. 12 reapers cost 12 supply which is the same as 6 marauders
7. a mass rax setup spamming marauders still generates overgas because maras are more mineral then gas intensive, thus as you are low on minerals you can almost always spare 600/600//12 for a round of 12 reapers compared to 1200/300//24 for the marauders
8. when cleverly burning a group of reapers on your opponents production facilities you often get to see their exact setup and probecount.
9. when frequent harrasment occurs protoss is forced to idle defensive unitz in his bases as cannons do not protect from big amounts of reapers.
10.well microed reapers eat dark templar and zealots for breakfast, giving you a good method to deal with sneaky zealot/dt pressure
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the above are the strong points i could think about
weaknesses
1. insane production time
2. low hitpoints ----> reapers have about 0 usage in a real battle
3. reapers are gas intensive ----> they conflict with any tech related builds
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now i think i can provide a scenario where reapers will be useful.
TvP - taldarim
http://sc2assistant.com/pics/maps/taldarim_altar_le.jpg[/url]
terran is powering low tech with high eco ---> mass marauders big rax play some medivacs etc.
protoss is doing a typical deathball style with colossus ht blinkstalker zeals etc.
usually terran will be maxed out before protoss, therefore accumulating money
while protoss on the other hand is still getting a scarier army with every cycle of unitz that is coming down.
so terran needs to transition away from his marauder med viking to a more supply efficient army or pick uphill fights against a stronger protoss deathball
what terran needs at this point is to get the air and vehicle upgrades, aswell as the infrastructure to support whatever latelatelategame army, he neglected in his opening stage in order to get the bio high eco play going.
this is where the reapers come in handy,
to punish protoss for moving out,
still make use of the mass rax
buy time.
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as a general rule of thumb: scan'n'hop! and have fun!