I don't believe you can do better than the Orvis Helios 11' 7wt Switch. Because it's so light, you can cast the Rio Outbound with a single hand using your double haul. 80-90 foot casts are the minimum. That being said, I use a standard single-handed 9' 6wt for my SRC fishing and only break out the switch for coho.
Leland.
PS, I am not biased because I'm the fishing manager at Orvis. My single handed 6wt is a Sage SP and I fish CND speys.