The steel cheese cutter I have I modified a little with a simple paper straw glued to it, to be used as a lead/limiter for the loaves I cut - and I get perfect bars every time. I understand however that for some people that may not be enough, it all depends on your particular needs.
I've also tried cutting with one that has adjustable bar at the end and slot where you insert a knife or a dough cutter, as well as a simple plastic mitre box - and I'm disappointed at how limited you are to the dimensions of the loaves you can cut, as well as the wide nature of the slot. It makes for a wobbly experience and crooked sides for me.
That’s why I prefer the cheese cutters, they don't limit the size of the loaf to that extent and give you even cuts. And depending on the wire you use, it can cut as narrowly as possible, preventing bars from splitting unevenly and breaking (which happens with knives and even some dough cutters - depending on the width of the blade and at what point you cut the soap, whether it gelled or not, etc.). For people who are not looking into professional type of equipment right away (even for more experienced soapers who don't think it's worth it for them to invest in a bigger, bulkier device), these are perfect and can go a long way. The cost of the wooden and the steal one was in the range of 11-13 USD each and to me, it's worth it. Of course, if you are good with that stuff (or you have someone around you that is) - you can make something similar yourself and that will be even cheaper.
Yes, there's nothing wrong when people want to dive deeper, it's good to see so many options suiting different tastes and needs, and people being able to get more professional and effective in their work (getting a multi wire cutter, a log splitter and such). What I suggested initially was intended as a low cost option aimed at those who are usually hobbyists (even though pro makers still use them, depending on their production volume) and just want to cut great bars without spending extra, who don't have much space available and all that. That's what impression I had when I read the OP - sadly, they didn't respond after that and we'll never know if that's true.
Either way, IMHO, it's good for everyone who reads the thread to know they have different options and they don't need to spend a lot to enjoy what they are doing and do it well at that. This post is not aimed at anyone specifically, just don't hate on the cheap stuff - for some of us it's the bomb and we love it deeply
