components SRAM APEX VS SHIMANO

SRAM Apex is entry level/enthusiast gear - capable of of going the distance but heavier than SRAM Rival, Force and Red groups. Apex = lowest for competitive bike, Red = Highest. Between Rival-Force-Red the difference are materials and weight. Generally they function the same.

Shimano Tiagra is ~ equivalent to Apex. Shimano 105 to Riva, Shimano Ultegra to Force, Shimano Dura Ace to Red

There were some problems with Sram Red front derailleurs in 2011. Generally speaking both Sram and Shimano make good stuff. I would take Ultegra/DA combo if both are new. If it were a Force/Red combo it would come down to your preference. 

Well first off you are comparing SRAM's entry (lowest) level group to a combo/mix of Shimano's top two groups.

Generally speaking Apex would be best compared to Tiagra, Rival to 105, Force to Ultegra, and Red to Dura Ace

Shimano shifting is better that SRAM on road bikes. I miss shifts every ride in my SRAM bike, but I don't miss shifts on my Shimano bike. SRAM has a single lever for shifting up and down on the rear  derailleur. In order to go to a larger cog, the lever must first go past the position that takes you to a lower cog. Shimano has one lever for up, and a second for down.

Shimano vs SRAM on tri bike is a tie.

I agree with most of what everyone has already said, but I'd say Apex is closer to 105.  SRAM doesn't have anything as low as Tiagra/Sora in my opinion.  One thing SRAM Apex will do some others won't is handle a wide range cassette in the rear.

Agree with the Apex is equal to 105 and the fact that it is a bit more unique in that it is set to handle a wider range cassette.

Not sure what you guys mean by missing shifts, my SRAM Rival on my CX bike is pretty well set-up and I don't ever miss any shifts.  Though I don't either on my Shimano stuff.  Might be all in how it's set up.

It is all pretty much the same except for weight.  

I feel SRAM Apex is pretty darn good however, especially SRAM Apex compact for climbing hills.  

I have had Shimano 105 and Ultegra ... I prefer SRAM all day.  If you are a beginner, stay away from triple shift!  Nightmare.

Might I upgrade to Red or something sometime, maybe?

But unless you are a true pro ... Apex.