If you want superb reliability AND versatility, these have to be the #1 choice. I have three, in addition to a couple of older Plus IIs.
In case you don't realise, the Plus IIIs transmit the dual-level button function so, if you want to, you can initiate autofocus separately from the shutter release. Plus IIIs have two-level "Test" buttons with very distinct pressure differences between the two levels.
All Plus IIIs can be used in either transmitter mode or receiver mode, together with additional mode options.