The Icom 400 pro is the best UHF on the market, it's a25 watt commercial pro model tuned down to 5 watt, it's build quality is faultless. There 440 ( remote head unit) is not a commercial pro unit but still made to icoms very high quality and is one of there few non comercial products. Matched with a good attenna these pretty much out perform most UHF. All the other UHfs are made for domestic applications but still perform very well in same. My biggest gripe with the remote head units is they are not as easy to change channel or settings as a din model. I have an old GME in the ute that's been flogged to death and still going strong, love it's simplicity.
With attennas that's been covered well, just note that stainless whip attennas will fail on diesel vechiles due to vibration, it will take its time with modern vechiles but thy do work harden and crack, I have seen it twice and if you can get your stainless bit back you can ussaully fit it back in and go again ( they crack at the mounting into the elevated feed) although I don't like the way the attenna top bounces over the bonnet at speed.
For very high quality fiberglass and rubber attennas check out ZCG scalar, Australian made and not much difference in price to the other brands. There fiberglass 1.1 m up have stainless caps to protect the aerials top from car parks etc.