There are a few expensive brush pens out there. The first one I ever got was a Kuretake No. 40 Brush Pen, which is a lot cheaper now, but in 2012 it was $66 big ones from Jet Pens. It worked pretty good for a while too, until the brush tip formed a split. They were kind enough to replace it, but that was a one time thing. After the tip started splitting again, I began looking for alternatives. After months of looking for a decent weasel hair brush pen, and after using a bunch of synthetic haired brush pens and feeling they didn't have that snap, I find the Platinum CF-5000, what I had hoped would be my holy grail of brush pens.
Russel Stutler's post about the Platinum CF-5000 in his brush pen round up probably sent me over the edge to getting one, and he and maybe 3 other people have talked about it on the internet since. I had to have one to find out how it actually was. So I purchased my first one from Goulet Pens for a whopping $71.50 American US dollars back when they still carried them. It came in the mail, and had a pretty impressive packaging for most brush pens, with a box and a whole one ink cartridge (ink that is not the standard Platinum Carbon Black Ink but a variant they make for their brushes that isn't as good). And for a while, it was pure heaven.
At the time, I was using exceedingly rougher papers, because I was into texture. But because the Platinum CF-5000 brush pen bled ink like a stuck pig, it left some pretty crisp line work, and it created a line I really liked. It was a pretty great combination. The tip of the brush was a little longer than the Kuretake No. 40, and more narrow, making it a little easier to control, and it was a similar look to the tip of a nice Windsor Newton Series 7 Sable No. 2, which was my dip brush of choice. Great snap, made gorgeous lines, what more could you ask for?
Pretty early on I noticed that the fuller the ink cartridge was, about 100%-85% full, it would have a slightly dryer flow, which I wanted since at times there was just too much ink flowing through the pen. I ended up starting to manually refill the cartridge nearly every time I used the pen. Which, at the end of the day, is almost as much work as just pulling out a bottle of ink and a dip brush and inking that way. If I didn't do this, the brush tip would be absolutely full of ink at times, to the point where you'd never be able to do careful line work, and would either have to waste a lot of pretty valuable ink blotting it out, or refill the thing again in a 5-10 minute procedure. I almost considered having two going at all times so on the go I wouldn't have to worry about refilling it.
Then the brush tip began to have issues 2-3 months in, it developed a weird extra long hair in the middle, making it crazy hard to ink consistent tapers. Then after clipping that extra hair, not long after I closed the pen at a wrong angle and frayed the tip. It never came back together right after that. At this point, I needed a new tip. Which is an issue with a pen isn't super widely available in the US, and also everyone who was carrying it ceases to (JetPens did what looks like years ago, and so did Goulet Pens, but no longer). Not only that, brush tip replacements at the time were $30~ dollars, which is the cost of a whole Kuretake No. 40 now on Amazon or JetPens. Going to the Japanese resellers on Amazon, you could get it for $15~ or so, but that would take 4-6 weeks to ship, and then because that method is so insecure you could just end up not receiving your brush tip (like I did on two occasions). This is all less than optimal, and gets crazy expensive.
Now, don't get me wrong. I'm not a person that believes a brush pen should be a lifetime purchase. But I believe that a tip should last, at minimum, 6 or so months for how often I used a brush pen. Especially when that tip costs as much as a full brush pen costs for most synthetics, and on average most of the synthetics last 2-3 times as long. I ended up buying 3 replacements tips and a full replacement pen at a point when I couldn't source just the tip replacements. That's just crazy town.
This lead me to the all encompassing question: is this pen really worth anywhere from 2 to 10 times the price of any other brush pen? No. Hell no. It's good, in fact it's probably one of the best brush pens ever when it runs right. But for the price, and the difficulty of keeping all of the parts in order to keep it in tip top performance, I could just use a Pentel Pigment Ink Brush Pen - Medium XFP5M, which I can buy nearly everywhere online and even in physical stores near me for $6-10 dollars, has just as many hiccups (less, even) than the Platinum CF-5000, and quit worrying about the "perfect brush pen".
So that's what I did. I stopped using the Platinum CF-5000 all together because it's just too much of a hassle. Brush pen's are supposed to be portable brushes that you don't have to think about much, just use them and enjoy. I just wasn't enjoying myself much using this pen, it was torture in between the good times, an expensive torture at that.
A few final insights on the pen, I never personally had a issue with the pen drying out as some people always fear with using Platinum Carbon Ink. I just pulled out my Platinum CF-5000 that I had in storage for a year or so plus, and it flowed like a dream. These pens are supposed to have some proprietary seal that Platinum has created to keep them from drying out with their ink in them, similar to the way their fountain pen caps are designed.
And if you ever need a quick tip replacement, the Yasutomo Kaimei Fountain Brush Pen with Natural Hair Bristles, 7 inch Barrel #255 has the exact same tip as the Platinum CF-5000. It's extremely weird to me that these two companies had the same tip, but i compared them both extensively and they had the same length, diameter, and markings on the tip as each other. So I'd say they are most likely still the same, unless they've changed anything since 2017. Or you could just buy this brush pen as it's usually cheaper, and if all you care about is how it functions versus how it looks, it's basically the same pen.
Now, in a perfect world, when this thing is running amazing, and money is no option, this thing is a full 5 star product. But this isn't a perfect world, and this isn't the holy grail I was hoping it would be. Taking everything into consideration, the Platinum CF-5000 gets 3 Zaffino Crazy Face Frank's out of 5.