I pretty much use whatever I am carrying, but when I am going to be doing some work or cutting something particularly nasty that will damage the edge, scratch, etc. I will reach for something not so dear. At work I have a Milwaukee folding utility blade for just such things.
When I am going to be outside working on the vehicles, etc. I like something with a pocket clip so I don't have to try to dig in my pockets with greasy nasty gloved hands, so in that case most of the time I will use my Buck Bantam 285. For one, it is awesome and is an excellent cutter, and since it can be had for $30 or less, I don't really care if it gets damaged. Despite this, I have been using it for many years and it has lasted well.
If I am going to be doing some heavy duty cutting, then I like something with a wider handle that is more comfortable in the hand. In these cases I like something like a Sodbuster, or maybe my Buck 110 or 112 or a comfortable handled fixed blade (Mora, or one of my Marttiinis, or something like my Ontario SP1)
As an interesting side note, I realized this year that I really like having a small fixed blade in a belt sheath with me while fishing in my boat. Easy to access, something cheap so I don't have to worry about if I drop it in the lake, etc. Also something stainless so I can use it to open MRE's for lunch, and don't have to worry about getting wet, etc.
I saw a 3 Pack of plastic handled paring knives from Dexter online for $25 and decided to give them a try. Gave one to my wife to use in the kitchen, and dropped one in a leather sheath to use as a fishing knife and have the 3rd as a backup. These things are awesome!! Calipers read .045 thickness on the spine, so it is super thin and flexible like a filet knife, takes a screaming sharp edge and cuts like a lightsaber
I wouldn't recommend using it for bushcraft, but for general cutting duties on the boat it works great!
