Kenwood 3100 series vs Midland GXt or similar

I’m about to invest in a couple 2 way radios for my wife and I to use for bike-to-bike communication. I’m trying to decide if I should invest $$$ in a set of Kenwood 3101 radios programmed for frs/gmrs or get something like a good set of Midland GXT radios

My requirements are:

Decent real world range
The radio will likely be laying on it’s side in a tank bag or luggage not the ideal location, but mounting it vertical my not be possible. (In urban areas we’ll likely be within 1/4 mile of each other, but in the back country on forest roads 1/2 mile would be the norm)

Long run time
We usually ride 8 to 10 hours a day and often ride for 2-4 days without being near power. I could get a couple 12v chargers and 4 sets of NiMH batteries, but I’d like to make it a full day on 1 set of batteries.

Mic/headset plug
These radios will be integrated into an existing communication system so I need mic and speaker out ports

From what I can tell the advantages to the kenwoods are:
Availability of battery eliminators
Removable antenna. ( I could mount it remotely to increase range if needed)
2 watt transmitter. I can’t seem to find real power specs on any of the typical “consumer” radios

Is there anything else I’m missing? I’d get this right the first time and not invest $80 in radios and $50 in cables to find out I should have just spent an extra $100 or so the first time.