Only you can truly answer this question. Let's break it down:
Instance boosting with RaF XP // RaF Summoning
Code:
PRO
- Fastest route to level 60
- Very little time wasted to immediately setup your keymaps/team [You start boosting by level 10 at the latest]
CON
- You don't learn your class(es) from level 10 - 60
- Mindlessly grinding instances repeatedly
- Limited to 4 lowbies at a time
Instance boosting with RaF XP // No RaF Summoning
Code:
PRO
- Second fastest route to level 60? :)
- Very little time wasted to immediately setup your keymaps/team [You start boosting by level 10 at the latest]
CON
- You don't learn your class(es) from level 10 - 60
- Mindlessly grinding instances repeatedly
- Limited to 4 lowbies at a time
- Having to run your team to each instance [Unless you have other means of summoning]
Instance boosting with No RaF XP // No RaF Summoning
Code:
PRO
- Very little time wasted to immediately setup your keymaps/team [You start boosting by level 10 at the latest]
CON
- Slow route to level 60
- You don't learn your class(es) from level 10 - 60
- Mindlessly grinding instances repeatedly
- Limited to 4 lowbies at a time
- Having to run your team to each instance [Unless you have other means of summoning]
- You will be stuck in each instance for a much longer period of time because you are receiving the regular amount of XP.
Questing with RaF
Code:
PRO
- Learn your class(es) / team from levels 1 - 60
- Can use a full party of 5 characters
- Get to see the old world? :)
CON
- Slow route to level 60
- Become a possible target for the opposing faction [PvP servers only]
More may be added as I see fit 
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