This will not go over well with people - switch pros users are like apple fan boys - I am one of the latter ...
But I like to always be honest, so you need to hear all the info IMO
Choice 1 - Keep it simple for reliability and lower cost is using good old K4 switches and relays Only where you need them.
Choice 2 - go for the cool all in one panel - Switch PRO'S is a solid state MosFET based system EE degree comes in handy sometimes. Its generally really reliable and the company did some good work to ensure against the typical over voltage failures that technology has (Same tech essentially used in car amplifiers for stereos). But since its all in one, if it fails, you are cutting wires and wiring around it. expect to get towed.
If you used switches, you can 99% of the time jump them and be running in minutes to seconds.
I have installed many types of MosFET switch boxes including switch pro's and relay based switch boxes over the last few years, and none have failed, but I know some that have. And partially its because the wiring was poor and shorted blowing the box or the alternator lost a diode (that happens to and MosFETs don't like 16v on the gate. Some smart people buy a companion plug they can just jump wires on and are never stuck or keep and extra around.
The switch panels (the keypad) last a long time since they are basically as reliable as a computer keyboard (similar tech).
With all transparency ...
I run a MosFET based switch panel in my car ... not a switch pro though, only because mine is jumpable in seconds - its not neccesarily better - its just better for me
I would not go back to switches personally and I love starting with a keypad - its just cool, but I understand how to get around a failure. All electronics fail - some are just better "protected" than others.
If your car has a non OEM ECM its likely less or equally as reliable than the switch box (except MoTec - they are tanks) ( I carry a spare ECM and all the sensors too).
Since you are wiring it yourself - you will have the best chance of never being stranded with an electrical failure ...
So bottom line you can't go either way - just plan on working around a box failure if you use an electronic SS system