I was reading on the RSWiki and how people labelled Bandos Chestplate as a 'power' armour. Although I know that the Bandos Chestplate has less armour and life point bonus that Verac's Brassard (what I'm using at the moment) , in what situations would you use 'power' armour and 'regular' armour?

Power armour works for almost everything, like Slayer, small to mid bosses (Glacors/QBD etc), and DPS roles in the bigger ones (Nex/Vorago). Normal (tank) armour is specifically useful for tanking the bigger bosses like Nex/Vorago/KK; in most other cases the extra defence/LP don't matter.

generally speaking power armor is better than defensive(regular) armor because the power armor has an offense damage boost and less health and defence rating and the other armor does not but has more health and defensive rating power armor is much better for more dps resulting in faster kills and the defence/health provided by defence armor is negligible except in a few niche areas such as tanking nex or kk

As covered above really, but just to add a couple of bits more:

There isn't really 'normal' armour. All armour is now Tank, Power, Hybrid or All

As Sara covered power>tank in basically everything bar a few specific top end boss fights, the reason being the amount of defence and lp GWD armour is more than enough for most monsters, the extra garnered by using barrows etc. does not do enough to really alter how well you can survive or how fast kills or trips are/ Conversely the damage booster on power armours does have a notable impact on you DPS meaning faster kills, which in turn mean you take less damage.

 

If it's not Nex, KK or Vorago (and even then only if you are going to be the tank) you should be using power armour over tank armour.

It's probably fine for dps to wear tetsu at Vorago tho