All a matter of what size suits you. Same knives other than that. Both are smaller than I like. I like the Duke size, even the 501 is small for my tastes. Have pictures but my photobucket wont load for some reason
I agree with fritz, the Knight (505), Prince (503) and to a point, the Squire (501) are too small for me. Here's a picture showing the four in the series. Top is the 500 Duke, next down is the 501 Squire, next the 503 Prince and then the 505 Knight. I don't have any of the wood handled 503's or 505's to show as comparisons, but the handle material doesn't affect the size. The 500 is about the same size as a 112 Ranger but thinner to give you a sense of scale.
I have a 500 and a 501. I also have a Camillus lockback #2, similar in size to the 505. Hence no 505 for me. I'm still waffling about a 503. But as I seem to lack the gene for must-complete-the-series, the 503 and 505 may never get bought.... Don't let that stop you, however. These are good knives, well made, and very pocketable even the 500 can fit (just barely) into a jeans watch pocket.
2 1/2 years later, I have a 501, 503, and a 505 - although the 505 is actually for my daughter when she's old enough. The 505 is definitely too small for edc, in my opinion. The 503 and 501 are great, although I wish they'd add a third pin so the scales don't move at all...
I appreciate sering the pics of all of them together. For what it's worth, my 505 is perfect for a small pocket knife, it teams up well with a 112 or 110.
505 is perfect size for the little coin pocket in your jeans. I have a 500 Duke also and that is an incredible knife in my opinion too.
I've owned two 501's. Of the 5xx series, the Squire is my favorite for EDC rotation. One that I owned is long gone because I wasn't happy with loose scales and the other is at Buck Repair right now, because the blade won't stay closed. Shake and the blade rattles when closed. Turn it "up side down" and the blade falls out about 1/2 inch and it was a brand new knife. I have delivery confirmation that Buck has had the knife for one month now ... and I haven't heard one single solitary word from Buck at all, via email or anything else. Buck repair site states that repairs this time of year could take up to 8 weeks, so without any communication, I'm just holding my breath and crossing my fingers I even get the knife back and if I do ... hopefully it works. I've got a 55 too and even with it's diminutive size, it has one more rivet on each scale than the 5xx series. The 55 scales aren't loose nor likely ever will be. But the quality of the 55 is a whole nother story LoL and the imperfections noted (soft springs, plenty of blade play etc), have been accepted as just how Buck is these days and I knew that going in. So yeah, Knight vs Prince? ... 501 Squire
I agree with the above - the 505 is just a bit too small in the handle department... hard to get more than 2.5 fingers on it, even when putting your index finger on the choil. The 503 is a happy medium of pocket-ability and grip. If I had to choose between the two, 503 hands down. But the 501 is definitely more comfortable if you are doing a lot of cutting... but still not nearly as comfortable as the 112... My recommendation would be to buy the 503 now, but start saving your money for the rest, you will probably end up with several
