I have a secret labs Titan. It's been okay for me for the last 12 months and I'm weird about chairs - as a rule, I usually find any office chair I sit in deeply uncomfortable and distracting.
I love that the Titan is very firm. Like super firm, to the point where people who like smooshy chairs hate it. But it really is the firmest chair I've sat in, and when my posture matches the chair, it's very supportive.
Unlike ergonomic chairs though, the range of adjustments is not amazing. It is adjustable - back, base tilt - all the usual bits, but the shape of the back of the chair is quite rigid, so if you sit in a weird position, you may find it uncomfortable over a long duration.
The only other negative for the titan is that the rubber on the arms has started to crack and tear and this is quite a common complaint, judging by le internet. The latest 2022? models address this by making the tops of the arms magnetically replaceable, so I'd imagine this is less of an issue with the newer models.
My mindset is very much like yours - I'm using the Secretlabs chair in the short term, with a view to upgrading next year (I'm thinking about the Steelcase Gesture, although I really want to find one to sit in before I spend that much on a chair). However, I have used the Titan for a daily driver for the last year in 8-12 hour spells and if anything, I have less aches and pains than I did in the 'ergonomic' chairs that I used to sit in at my old office.
PM me if you do decide to press ahead with a purchase, as I have a code that can get you a discount. It'll give me something too, but I think it's just a lame cleaning kit or what not, so whatevs ¯\_(ツ)_/¯