I've been searching for reviews of the series 0 traveler tripod (GK0545T-82TQD or GT0545... without head) all over the place, but found very little. It seems that most people use its bigger brother the series 1 version.
I was hoping to get an idea on how sturdy and practical it is for travel with a mirrorless system.
I've got an older model (0531 I believe) and use it almost exclusively for travel with my mirrorless cameras. I use mine in conjunction with an Acratech Ultimate Ballhead. It's a very compact setup, and quite light which is nice because my idea of vacation is hiking in the woods.
Performance wise it works well, but definitely has limitations. Generally speaking with lenses under 50mm I don't think I've noticed any stability issues. I adapt a Canon 17-40L to my Sony A7 and do 30 second exposures throughout that whole range with no issues.
It's when I get around 100mm I start to notice the limitations. I was shooting a night scene with my 100mm macro and anything longer than about 10 seconds I was getting some blur, even on a calm night. 5 seconds or shorter seemed safe. I also have a m4/3 setup which is super light with the small primes and I can do a little better with that.
Overall I'm happy with it, don't feel the need to upgrade. But if you shoot longer lenses, or do a lot of long exposures it's probably worth looking at other options.
I use a Gtizo GT-0540CF tripod, with RRS BH-25 head, as my light-weight travel tripod. It gets used about four times a year (in checked luggage), and I've had it since June 2018. It's in fine shape, with some knocks and scrapes. One of the main tubes came loose in the leg holder assy about five years ago. I glued it back with epoxy, and it's been fine since, as have the other, unglued legs.
I often use the GT-0540 with gear up to a large-body DSLR with 70-200/2.8 L IS II. It works just fine, as long as the rig is well-balanced. With the heavier gear, I often don't extend the lowest leg sections. It's not as steady as my 'normal' travel tripod (Feisol 3441S), but it's very light and way steadier than handheld or monopod. I used it fully-extended earlier this year with a M5/SL2 travel kit.
I have the Leofoto LS-284C and have been happy with it. In fact, the more that I use it, the more that I like it - lightweight, stable (considering it's light weight), and relatively inexpensive. I know that it is not one of the tripods that you mentioned, but thought that I would just throw it out there if you have interest. A recent discussion thread for it is: https://www.fredmiranda.com/forum/topic/1534140
