Mine lived about 17' from my boat lift for years tying up flies in FL and now lives in the mountains of CO. If there's a better alternative I'm not against switching but I've yet to see it and am open to an explanation.
Jaw is too short and blunt- so the thread contacts it when hanging toward the back of the hook- and you have to avoid it when doing wraps back there. And while "true rotary" is possible, it's not easily achievable- because one angle adjustment impacts the other. Then when you get close to the proper position, you have to adjust the hook position to make it level. You can get close (usually the case when I gave up), but bang on is easily achieved with other designs.
If they made a trout jaw, I'd have probably have kept it. Watch a Davy McPhail or FeatherBender video- you will see how much better access around the back of small hooks can be. The jaw doesn't have to be in the way like it is on the Master.
I concur with osseous, space around and behind the jaws is so important for me, especially if one prefers to put materials on a fly hand over hand without using the rotary function. I use a dyna-king pro and it is all I want largely because it doesn't have features and functions that I don't require or that would be lost on me with my tying 'style'. Basically I want a vise that stays as much out of my hands' way as possible and holds my hook range use with no spitting or slipping of any hooks from size 30 to 2/0. So look honestly at your tying style and hook usage, perhaps a vise will not suit you if its jaws aren't shaped to suit the way your hands work at the vise; perhaps some jaws just hold your hook sizes better... I know the DK Pro does suit my tying. Find the vise that holds your hooks but allows your tying style to blossom unhindered.
Well, this afternoon I needed a few foam hopper tying supplies so I stopped by one of the local shops and had an opportunity to compare the above mentioned vices as the shop I went to carries nearly every vice made. I put the various vices on the table and sat down to play with them. I could list the perceived shortcomings I see with the DK vice/s but in an attempt to keep this from becoming a pissing match I'll just say that it might come down to personal preference. If my home burned down tomorrow and I needed to replace my vise from a list of any vice made, after playing with most of the top vices this afternoon, I'd buy the same one all over again.
It's nice that we have choices so that different people can use different tying vises that suit their specific needs
A lot of folks love them- and that's cool with me. It's beautifully made- and kind of a bargain, given all the high quality machining. In my hands, a Law style jaw just works better on the flies I'm currently tying.
I think if I'd started on something else I would probably prefer something different but having decades of tying on various Renzetti vises it's just a "glove" at this point. It's probably a case of my not realizing what I'm missing.