I have the MP-1 vertical from Super Antenna.
It's an extremely portable HF antenna, great for carrying in a briefcase and using in compromised locations.
I have used it when I visited my mothers house last year, erected it on the bedroom floor. I did manage to work Spain on 40m. It's a good compromise antenna.
However I do find it difficult to tune, it takes time adusting the coil and fine tuning the telescopic section. In the end I use it with a portable atu, I get the antenna close then match with the tuner. It works fine.
I have not done any comparisons though, you may well be better off with a wire on the atu if you have the space to throw one up temporarily.
All in all a nice antenna, pretty well made and very portable but don't expect resonant dipole performance from it and it is kind of pricey.
wanting some thing portable for 857d, maybe the chapstick mp1, or buddipole, are these any good? any body got any others that are really good, or work.