My opinion and experience:
Nitro 1/8th scale:
Plus:
-Long 30-60 minute mains for real racing action with pitstops
-real engines are more fun
-lighter
-solid, steady rules.....when was the last rule change in this class
-pretty fair, noone has a power advantage
-sound awesome
-real brakes are fun to
-smoother low end power, less tire wear
-there is a sense of accomplishment to getting a finicky nitro engine tuned right that nothing in electric can compare to.
minus:
-glowplugs and fuel
- need to find a pit guy that you can expect to see at the same races your going to. (not nessasary but in long races pits are critical)
-Clutch maintenance
-oily
-airfilters
electric 1/8th scale
plus:
-idle really well for a real long time
-plenty of power, usually too much
-no pit guy needed
-no fuel
minus:
-short, lame mains
-no pit action
-heavier
-usually overpowered (some are learning that less is more)
-ESC's and motors are still unreliable and expensive, getting better
-tire wear (more weight +more power)
-sound like metal in a blender
-"waaaa, he's running 5 cell, I thought we were running roar rules...waaaaa"
There is just something special about the challenge of a long 1 hr main with pit stops that electric will never be able to touch. The sound and smell of nitro rules.
I'd recommend jumping into nitro. Just get a good reliable medium powered engine that will be easy to tune and maintain. Like a RB hobby 9 with a 2045 pipe.