Yes the UHE has a booster but that doesn't make any difference where you place the system, the temperature ranges are the same.
The MaxCap is a pretty beefy, heavy system and i wouldn't want to use it portable myself like with a faucet adapter.
It is mounted on the wall above the laundry sink and is fed from the washing machine cold water supply via a brass garden hose wye with the individual ball valves. I leave it pressurized all the time since it fills an ATO container but you could shut the ball valve on the wye too if you don't have it hooked up to fill storage.
Also when I had the regular 90 and then 180 GPD dual membrane MaxCaps, I added a drinking water kit that fed a drinking water faucet at the kitchen sink, another at the laundry sink, the cold wate rin the door of the frig and the icemaker. All of that was isolated from the DI by a check valve as Spectrapure shows in their drawings. I could have pressurized RO water or make DI directly from the RO membrane avoiding the TDS creep present in drinking water pressure tanks.