The MONR31 is a great antenna for VHF hi and low band and works good on UHF. Not too sure on 800. The vehicle version of the MONR31 was very highly regarded in past years because the low band portion resonated right around 42MHz and it was the best antenna for monitoring the CHP around here. There was a version that had a choke sleeve below the coil that supposedly improved 800, the mobile version of this was the MON52 or 53.
The MON64 is the same as a Hustler Discone, which only has three top and bottom radials and is more of a joke than a Discone.
prcguy