Sourabh Vyas

Focused Sales Manager committed to motivating others and offering extensive knowledge penetrating new territories and promoting product lines. Highly effective mentor driven to assess individual and group performance to implement improvements and set goals. Determined individual with background in establishing and nurturing lucrative partnerships.

You are free, responsible and independent to take the decisions you want. You want to take the more difficult but scenic path, or you want to take the faster route, it is on you. You want to stop for a break or ride 600 km at a stretch, it is on you.
Solo rides are always faster. Unless you end up basking in the sights more than normal, you are always quicker. You can set your own comfortable pace.
In my opinion, riding solo in most cases is a safer option. You don't have to deal with newbies as part of your group. You can maintain your own comfortable distance and speed with traffic. You are not bound by the group rules (if any).
Flexibility of control over itinerary.
You are also on your own when it comes to unforeseen incidents like breakdowns and accidents.
Group rides are a nuisance as seen by general public. With riding gear, loud exhausts and fancy toys, that feeling becomes all the more pronounced.