In red Orchestra the spawn time for a lot of maps is 15 or 20 seconds, the spawn time in a game like counterstrike after dying is like 5 minutes. I wouldn't call 1500% of the time a respawn in Red Orchestra takes similar.
Sure it looks similar to the principle of buying, but that is exactly because that is something people can natively understand and grasp. You can spawn either 20 times with a rifleman or say 5 times as a sniper, it increases the rotation rate among rare classes, and actually gives an increased value to the more important classes. And classes that are supposed to die more could be allowed to die more like for instance smg soldiers.
By default without some changes individual reinforcement can have some issues like the entire team running out beside a few. Although these effects can easily be minimized by for instance resetting the reinforcements as I said in steps, like after certain time intervals or obtaining certain cap zones. Next to the ability for people to give some of their lives to other players.
This means that a player that runs out of reinforcement will soon be able to play again, and will encourage his team to actually survive rather than die (as once they cap something you can play again).
Another thing you need to remember though is that in other games with limited individual reinforcements people would end up adapting their play to the reinforcement level, if you die too quick a few times people end up playing more secure for instance. Generally even if in a 30 minute game people only had 4 lives hardly anyone would be without reinforcements.
Individual reinforcements by default do not make people camp or not, but it makes people aware of the reinforcements. So if the reinforcements are low they play campy and if the reinforcements are high they will play more aggressive.
And that is the great thing, in RO if a mapper gives a map low reinforcements it only means that the team will run out of reinforcements quicker it generally does not change the way people play. With individual reinforcements people individually see the effects of reinforcements and adapt to play in the best way possible that allows them to stay alive, and that is why you generally see that hardly anyone runs out of reinforcements.
If reinforcements are in the game, then in any way possible people should be aware of how they individually affect it and be appraised for their usage of reinforcements. Direct feedback is the easiest way to generally make things clear to people.