I've built 3 Geckos with the Takeuchi TG5W bridge (plus one more on order) as well as 5 Geckos with the Kahler 7450.
The Takeuchi bridge is a good value, and is moderately adjustable for most uses. However, on a Gecko bass the saddles are just too tall for my needs. I've used a Dremel to grind down the tops of the saddles to get nice low fretless action. It took a bit of effort, but the result was satisfactory.
The only remaining issues are that the Takeuchi saddles don't stay firmly against the bridge plate without the strings at tension, and there are only two small contact points between the saddle and the bridge plate - i.e. screws to adjust the saddle height. This doesn't exactly make it a rock-solid bridge with maximum tonal transfer to the body. It works well, but it could be better. However, at $70 for the chrome plated version, the price is very nice.
I really prefer the Kahler adjustable bridges. They avoid all of the issues with the Takeuchi that I've mentioned: the saddles can be adjusted lower by default, they stay in place better, and the contact area between saddle and bridge plate is larger. True, they cost more ($109 on eBay for a 6-string in chrome) and they take more time to set up properly and adjust, and they practically require a route on the body for a recessed bridge plate. But in my opinion, you do get what you pay for.
I don't have any experience with Hipshot bridges, but others have said good things about them. They can be found on eBay for around $75.