HSS, High speed steel is a very good quality material, if it is a brand name set that will be fine.
TiN Titanium Nitride, is the gold coating, this is a coating that will give more life to the tip of the drill, and will allow you to run faster in a roduction enviorenment. when you sharpen the drill you loose it on the edge but it still is on the flutes, so still has a 20% advantage on an uncoated tool. However many cheapy brands use a lesser quality HSS and coat it, so personally I would say no, unless you want ' the look' !!
Cobalt, is a percentage of cobaltum added to the HSS, either 5% HSS-E or 8% M42. This gives the drill much more core strength. If you were drilling a lot of stainless or tougher steels I would suggest this. It does make them a bit more brittle as they are harder, but they will last a lot longer and stay sharp longer if used correctly.
Personally if it is for general use I say go a brand name HSS set as you can sharpen them properly with your drill doctor.
I don't know brands over there so i can't suggest any, however, try and get a set that has shiney flutes, that mean they have had the flutes ground, which is better than a milled flute.
On a quality set you may also see a thinned point on the larger diameter drills, this is good, however if you can't put it back in when you sharpen the drill it also is a once off affair and will have a thicker web.
I hope that helps
FYI I worked for a German company called Guhring, one of the top tooling manufacturers in the world, and no I couldn't afford one of their drill sets either !!