5w uhf handhelds

For years i have been using a set of 5w uniden UH073 radio's but i have finally lost one. There is a replacement in the identical shape the UH0750. I heard that the UHF channel frequencies have changed slightly and this radio won't communicate as well with my other uh073 is this marketing bullshit?

Also there are new GME handhelds specifically the TX6155 that apparently have a better battery life, there is a uniden radio that looks very similar the UH850S both of these radios look to be bigger and potentially heavier than the UH0750

Can any one who has had a play with these various radios advise?

@mikee for tech advice

As long as they all work on the New Zealand PRS Channels you will be fine. Uniden are OK and generally they are Backwards compatable.

There is a good deal here at the moment, base unit with free 2w Handheld

GME TX3120 Bonus Pack, Navcom Electronics Ltd

I prefer 2 1/2watt max in a handheld as they weigh less and with all the other crap we carry it adds up.

Both GME and Uniden seem pretty reliable.