Bentwings is right.. wow a five year old thread....
Here's my two cents worth. Drill presses are not only (what I consider) the most dangerous machine in a shop they just are not accurate especially if they have a table that can be tilted. A table that can be raised/lowered, turned and tilted isn't going to hold much of a tolerance unless it's made by Mori-Seiki.
Hole saws just don't make accurate holes. Maybe they're suitable for wood, however if you need a good fit between parts, don't expect accuracy. I actually thought about producing finer thread hole saws with a ground to size O.D. that might be more accurate. I don't have time to pursue that idea.
For drilling, I use a center drill for standard length drill bits and a jobber length drill before switching to an aircraft length if needed. If I'm on a CNC mill, I also use a center drill first, unless I'm using stubby drills and the accuracy of the hole is not critical - like when I drill a hole that I'm going to plunge into with an end mill.
I don't plunge an end mill into metal unless I drill a hole first that is equal to about 55% of the diameter of the end mill. This is to prolong tool life. Drills are cheaper than end mills. About 50% of end mill tool life is lost using it's full diameter for plunging.... unless you zig-zag or spiral in (about 1.5 to 3 degrees in Z) to improve tool life.
As long as I'm wasting your valuable street rodding time, let me give you an opinion on drill bits. Don't buy Titanium coated drill bits. I think they're a waste of money. Ti coating provides improved tool life, but only when used at proper feeds and speeds as in CNC machining. You will never attain correct feeds and speeds on a drill press or cordless drill. Any China drill bit that is Ti coated is still just a cheap steel and has no valve with Ti except to sell it.
Buy only American made quality drill bits. Check MSCdirect.com for a primer on drill bit choices. Vermont American used to be made in America and offered a lifetime warranty... no longer .