The Pax guitar saw is ok. I got mine for about £20 - its nicely made. Cuts on the pull. Cuts exactly 0.6mm as near as dammit. I have had no problem with it it and all my boards are ebony - and some very hard. Japanese saws cut ebony nicer I think - but its a job to get a standard blade at anything other than 0.5mm 0r 0.7mm.
Take a look at Deiter website - good stuff at good prices ( Pax Guitar 24 euro )
Bear in mind its easy to get fretwire with a 0.5mm tang. Many Japanese saws have 0.5mm set - but they are rather shallow on the blade so it makes it awkward to cobble up a depth stop.
Actually - a depth stop is not really necessary. Once the initial cut is about 1mm deep - its quite easy and accurate to deepen it freehand with the same saw if you are carefull. You need to do that anyway if the board need dressing when on the neck. But you still need some depth for a guide to be effective.