Having both of them at same time.
Comfort wise Lancer leads.
Seats are more comfortable in Lancer.
Lancer has more leg space for rear passengers.
Sunny is no doubt tougher car.
Engine wise less issues as compare to Lancer.
Having both of them since 2005. Both cars are used on same roads locally mainly.
Suspension wise both are good.
Maintainance cost is almost same for both.
Recently replaces front wheel bearings of both and ironically both share same wheel bearing.