About me:
I consider myself a decent Terran. I have matched and beat many grandmasters on ladder. When active on NA, I have managed to generally stay in the top 100 Terrans.
About Mech:
Pros:
1. Position becomes less important, but still important.
2. Much less micro involved. You don't have to worry about that single misclick losing all your marines to banelings.
3. Hellion mobility allows constant drone harass with runbys. Additionally(which I don't do in these replays), hellion drop harass is an option too.
Cons:
1. Game sense is the single most important aspect of this style. You constantly have to scan and be aware of your opponents composition.
2. Immobility can be a problem in some situations. It just takes time to adapt.
Some Zerg timings to keep in mind.
1. If you see them mining gas early on, try to keep your SCV there and see if they pull the drones when they reach 100 gas. If not, I play a bit safer and go less hellion heavy in anticipation of roaches.
2. I try to scan initially around 9 - 9:30. If they open with roaches, I push this back as they generally will be delayed a bit more with mutas. If I see a spire started, I'll start making marines out of 1 rax, throw up an enigneer bay and an armory. If they're zergling heavy, double evo chambers, or anything that makes me think I have potential to deal with infestors, I'll throw up a ghost academy.
3. Try to scan around 16-17 minutes for hive tech. At this point, I'll throw down additional barracks and make ghosts for sniping.
http://www.mediafire.com/?fjflp2bebbgav68
In this pack there are 6 replays. 5 are mech style, and 1 is a hellion/marauder timing which I enjoy throwing in every few games to mix it up. I've probably played about 10-15 games with Mech so far on ladder and it has been working wonders. I've lost 1 TvZ on ladder out of the past 10-15 or so, and that was me simply being alt tabbed on skype.
Build Order:
(Depending on size of map, I will scout with the 10th-13th SCV)
10 Supply Depot
12 Barracks
13 Gas
15 Orbital
16 Marine(only one marine, rest of the gaps are just SCVS.)
16 Supply Depot
18 Factory
19 Reactor On Barracks
21 Supply Depot
21 Command Center
When reactor is done, swap with factory. This should come around 25ish supply.
24 2x Hellions
30 2x Hellions
These hellions I generally wait for as a group and will contain creep and try to snipe drones or zerglings.
Here I will generally make a couple additional marines as well. These are optional, I just do so as there is some roach timings I worry about. I will also keep producing hellions constantly.
33 Supply Depot
40 Orbital on second Command center
40 Gas
42 Factory
48 Supply depot
From here, the Zerg has many ways they can react, so I don't feel a generalized BO is feasible. But at the 50 supply point, you should have 8ish hellions, providing good map control. As soon as the second factory is done, I'd generally tech lab, start blue flame and siege tank. This comes around 7 minutes(in game time).