The most expensive saw is one that does not work so you can't learn from it. A dovetail saw is a lifetime tool so consider that in the price.
After much frustration, early Tzack backsaw, a couple gents saws, a Dozuki and never could be consistent, I bought a Florip. Unfortunately Erik passed away, but it proved to me the saws were the problem. I could not learn with a saw that did not cut strait.
There have been several You-Tube "cut-offs" of dovetail saws recently. Veritas does well as does Cosman and Blue Spruce. (I think Green closed shop and moved to Blue Spruce which explains how good their saws are) Bad Axe did not do well which surprised me.
I also picked up a Suizan Dozuki and sure enough, it cuts strait too. So my first cheap one was junk. Gents saws just don't feel right to me. I don't know if any gents saws are well tuned from the factory as they usually are on the cheap end. I do OK with Japanese saws, but prefer the Western. Do try a Dozuki as a good one is $30, not $130. You may like them. They do better in softwoods than Western hardwood. Don't try to dovetail Purpleheart as you'll break teeth.
My early Tzack saw I thought was defective as the blade was not strait. After I sold it I found out all it needed was a smack on the spine to reseat the blade. I am sure well tuned, it would have been great but the TPI was a bit courser than a modern Dovetail. More like my Spears and Jackson I tuned up.
Best bet is to visit members that have different saws and see which one works for you. With a good saw, both Western and Japanese, you can then adjust your stance and practice practice practice. I never learned anything with bad saws. I learned a lot from a few trusted You-Tubers on stance and tilt once I got a trustworthy saw.
Learning how a saw should work, I was able to tune my mid-price ( S&J, Crown) saws as tenon rip and crosscut to cut strait. Yup, it is the tune, not the blade or even how pretty the handle is. A dovetail saw is even finer teeth and I have not progressed to that level yet for tuning. The difference between a cheap crappy saw and a expensive saw are how nice the handle is and TUNING. All the steel is about the same. Tune makes it work.
I have yet to come to terms with either a coping saw of fret saw. I may pay the price for a Knew and see if the saws are the problem, or I just need a lot more practice.