OK, first, I have to say that for about $400, you cant beat a JW Smith tactical framelock, strong, with the fit and finish you would expect on a $2,000 knife, I really think he is a great value, and his tacticals are underrated. I cant recommend him highly enough. $400 is a small price to pay for absolute perfection IMO. To call his knives smooth and precise is an understatement. You just have to see it for yourself.
Also, i guess youre talking about folders, but Scott Cook makes a beautiful snakewood and damascus hunter fixed for a very reasonable price and the workmanship is also as good as it gets. I imagine his Lochsa folders are equally well made and thus a good value.
Another underrated maker is in my opinion, Aaron Frederick, while he does make some beautiful, $2,000 art knives, he also makes a lot of affordable tactical knives, and again, workmanship is as good as it gets, and he uses a thick, very well fit liner lock. I have one of his with a CF handle, blued damascus bolster and a hand rubbed recurve that is both beautiful, and yet very strong. If you want a strong tactical knife with a little flair to it, he is a good choice for about $400.
It goes without saying that Tom Mayo's framelocks are strong and extremely well made, but since the prices have recently skyrocketed, i dont know if his knives are a good "value" anymore. Of course one could argue that his knives are so good, theyre still a good value.
Flame away, but i honestly think that a large Chris Reeve Sebenza is a great value as well, strong as any knife made, fit and finish are absolutely perfect, and i feel for $300 or so, it does represent a good value. Especially if you pick one up on the secondary market for $250 or so.
Finally, another very strong and robust knife is the Strider SnG series, they are well made, extremely strong and well, just plain cool. At $400, i think i got my money's worth, and it has become my user.
Oops, forgot about autos. Well, as long as you wait a bit for the prices to drop, and drop they will

, i think some of the Microtech autos are a decent value. The LCC in particular is extremely well made and strong, and for $200 is an UNBELIEVABLE value. If you get an Ultratech for $300 or so, i think thats a decent value too. I dont care what anybody says, Microtech makes a very good knife.
On a different note, despite the price of $1700-$2000, many people think a DA auto from Charlie Dake is a good value, since i do own one, i can attest to the incredible workmanship and materials that go into one of his knives and i have seen custom autos costing a lot more that i dont think were any better, so i would say, that makes him a good value, albeit an expensive one.
And yes, of COURSE i recommend the knives i have chosen to buy and keep in my small collection, why would it be otherwise, i buy the knives that i firmly believe are a great value and if i end up thinking differently, i sell or trade it. So, am i biased, yes, but thats the nature of this sort of recommendation question. All i can do is tell you what I think are the best values, and of course this will be reflected in the knives i have chosen to buy.
So, there you have it, my choices for a good value in the custom/semi-custom tactical market.
PS. I would bet that Brad Duncan's knives are a good value too from what i have seen and heard, but not owning one, i cant say for sure, but maybe someone else can chime in on that. Also, i have never heard anything but praise for Obenaufs, but i dont yet own one.