Earlier this year I invested in an ATS 8" portable pier. It was by no means inexpensive, but I very much wanted something solid for heavier loads with easy leveling adjustments and a pier-type configuration for less interference than a full style tripod. Around the same time I got an 1100 to run in parallel with my Mach1. AP also recommended it because I described how some of my imaging locations weren't very level, and this would make setup easier.
The top plate of the portable pier is fitted to receive the adapters for both the Mach1 and 1100. But I now use it only for my 1100 as I use the Mach1 concurrently with my older Berlebach tripod. The Berlebach has been a good and trusty tripod, but I was able to observe and measure underdamped oscillations with heavier loads. Additionally, I ran into more interference problems with the Berlebach when I wanted to image before or past the meridian.
Leveling is easy as each leg has a turnbuckle adjuster. I want to be able to level it well as I use a RAPAS for polar alignment, which I finally just got around to dialing in to my 1100. It works so well now that I (almost) don't need to do any further polar alignment before imaging.
Anyway, all the models already mentioned are good ones and you wouldn't go wrong with them, but I thought I'd chime in with what I considered and arrived at. It's been a good performer for me so far.