Sorry for the long response....
Don't mean to contradict @Broski and his experience, but I've wheeled with him and he is one of the more experienced 80 owners out there and he really wheels his rig and is an excellent resource of 80 knowledge. However, judging Slinky performance based only on having front coils isn't going to give a clear picture of their capabilities. The coils are only a piece of the suspension. IMO, the Slinky shocks play a larger part in the ride quality and performance of the Slinky kits. On a rock crawling rig, the shock performance is less important since the suspension cycles are generally slower and are not going to generate the heat that running shocks faster through the stroke over and over is going to, so a simpler shock will do the job on a crawler and the differences in performance won't be as apparent. The adjustable Slinky shocks make the differences even more obvious.
The slinky springs are thick coils, larger diameter wire than many other coils and that can be the reason for some having rubbing issues. Typically if there are rubbing issues, its on the factory bumpstop brackets on the bottom of the frame in the front, or on the lip of the bumpstop inside the coil if the axle isn't located properly and the coil has banana'd a bit. All I can say is that I have never had issues with my Slinky coils rubbing in the 5 years that I've had them. They also have maintained the advertised lift height even as I've added weight to the rig over the years.
Honestly, I can understand that on Broski's rig he prefers the Dobinsons. Rich, correct me if I'm wrong but the majority of your wheeling is on more difficult trails and is what most would classify as "rock crawling" rather than "overlanding". There aren't too many people out there that have much experience with both Dobinson and Slinky suspensions (beyond just a brief ride in one or the other that they don't own). But from people that do have experience with both its not uncommon to hear feedback very similar to what
@Bludozer posted earlier, that Dobinson's can feel "floaty" and Slinky's feel more "tight". For a rig that is primarily a rock crawler like Broski's rig that floaty sensation probably isn't that apparent, at least on the trail. Also, ride preference can vary a lot. Some people really like that floaty ride and don't mind not running any swaybars. Others want the rig to feel more controlled and have less body roll etc. Neither one is wrong, just different preferences for different uses. At the end of the day, you gotta find the setup that works best for what you do with the rig and that matches your preferences. FWIW, I've never heard of anyone that has had a complete Slinky kit that hasn't loved it.
The customer service issues from Slinky......I can't argue that there have been issues in getting and keeping the products in the US. There's a number of reasons for that and not one single place to point the blame. At the end of the day, it doesn't matter to the customer what the reasons are, all they know is that they either can't get the products, or can't get a response from Darren or from the US side. Today, I don't know that much of that matters since there is not a current US distributor or dealer for Slinky.
I do know that some have contacted Darren directly in Australia and have arranged for parts or complete kits to get sent to the US. That might be an option for those that want to try that.
It's no secret that I've weighed in on Slinky stuff pretty much since the beginning. I was involved as a third party for a while to assist both Darren and all the US distributors in answering questions etc online about the suspension. It's now been almost a year and half since I've had anything to do with the business so there is no benefit to me to say anything about Slinky stuff just because I was getting something out of it. I never did that before either, and have always tried to just give my honest impressions and information.
It does brings up a point about the communication, or lack of. Darren's shop in Aus is a small one and Slinky is just part of what he does. All of the US Distributors have also been small shops. Redline was just a few guys, Endless Horizon was literally a one man show, and even Millcreek is a pretty small shop (although the largest of the 3). They have all had shops to run and to keep in business (servicing vehicles not just doing online parts sales) so they have not had much presence on the forums or facebook groups which has been a big way that customers have tried to communicate with them. As for emails and phone calls, from my experience working with all of them I can say that none of them have intentionally ignored any communication but a lot of the time they couldn't get to those until after shop hours and they had families and personal life to balance as well. I believe they all tried to do their best to communicate but in reality its a big part that has killed the reputation and they needed more resources to help with communication. The bit that I was doing wasn't connected with order status or on the shelf inventory or international delivery schedule so I wasn't much help with any of that.
