I have a Bonanza co-ax -- the original coaxial predecessor to the Forster co-ax. I bought it used off the internet about 5 years ago, mostly because so many posters on this and other reloading sites were singing the praises of the co-ax design. And judging by the fact new ones are back ordered and used ones keep their value, I guess they're sought after.
I bolted it to the bench next to my RCBS single-stage press, and tried using it for a while. Some things I came to love right away: changing dies involves sliding the old one out and sliding in a new one, and you don't have to change shell holders. I didn't care for the priming system, but that's not important since I use an RCBS bench top priming tool so I get a better feel for the resistance of the primer seating.
My own personal preference, with both the RCBS Rockchucker and the Bonanza ready to go in front of me was that I preferred where the handle was on the RCBS. I had to reach up high to grab the Bonanza handle, while the RCBS handle was right at shoulder level and I was able to deliver full power throughout the stroke. Perhaps I could have changed that by mounting the press on a lower table, but then my knees would not fit under the table.
As it stands now, I am ready to sell or trade the Bonanza, but haven't bothered doing so because shipping would be kinda pricey -- it's heavy.
Just my 2 cents.