I have a TSF Beast and have owned a Strider PT for a longish time (5+ years, and I bought it second hand). The Beast is larger than the PT and carries heavier, but I find the dimensions more pocketable than the PT, which is blocky. My PT has been beaten on hard for a long time, and I've never had a problem with it. Much of its duty has been in salt water and sand (fishing, at the beach), and it never failed or rusted. I only took it apart and cleaned it for the first time a few months ago--even with sand in it there was never a problem. I have no blade play or lock-rock, and the knife is very smooth. However, I can't get it (with convexed S30V) to scary sharp. Nevertheless, it maintains a great working edge forever. The blade slices well at .125", the detent is the best I've ever had on a knife, and it locks up with a fantastic snap. It is also very light for such a solid strong knife.
With the TSF you have the benefit of great conversations with the maker, and some customizable options. The blade shape isn't sexy, but it works very well in nearly any situation. The knife is easily as smooth as the PT with a very strong detent. I don't love the thumb stud, which is very grippy, but it flies open with the right pressure, and locks up with a terrific click. The lockup is rock solid in all directions. The handle was too sharp around the edges when I got mine, so I sent it back and Jim smoothed them all out--it feels great in the hand now. I've convexed the edge a bit, and have no problem getting a really sharp edge on it, which it holds very well. Jim does a really good job with the CPM 154, and the grind looks great. He also has no problem with customers taking it apart (which I have done a couple of times already). The blade is thick--.157"--and the hollow grind very shallow, so it's not a terrific slicer, but it does well enough because of the steel. It's a blade you will happily use for prying (I know you shouldn't), or much tougher work than many others. There's simply nothing you could do to hurt it, and if you did, Jim would fix it, no problem.
In short, both are great knives and serve their purposes. The TSF quickly picked up corrosion at the beach and got cleaned and put away, while I carried the Strider. But on a daily basis the Strider is a bit too utilitarian for my EDC, and the TSF is nicer in the pocket. Both are smooth with excellent lockup and detent. Frankly, I'm going to have trouble deciding which to carry when I go to Borneo in a couple of months.
Of course, if I'm being candid, neither of these has better fit and finish or a nicer blade than my Spyderco Gayle Bradley--it's as smooth or smoother, locks up as solidly or more (with a CLACK!), or gets as sharp and stays as sharp with the M4 blade. The GB is just a little too big for EDC for me.
I hope that helps--ask more specific questions if you like.
I should add: I prefer to buy things from people rather than companies. If I had to choose between the Strider and the TSF, I'd choose the TSF because it's about the person that made it. It's not a perfect knife (I think that when you go custom you are more likely to have "personal" imperfections), but it's a great knife and supports better my own purchasing ethic.
Cheers,
Daniel